51fly国际课程 (51fly.win)

 找回密码
 立即注册

手机扫一扫,访问本页面

 

      

上传图片附件

未使用图片

小贴士: 允许的图片文件格式为: gif, jpg, jpeg, png, webp,上传完成后会在上方生成预览,用鼠标连续双击缩略图,或拖动缩略图,该图片就被绑定至本题,显示在题目下方

本次作答已使用

小贴士: 此栏目显示的是当前作答使用的所有图片,绑定到某一题目的图片同时会显示在该题目下方; 删除使用的图片会将其转移到<未使用图片>类别


习题练习:Physics Unit3: Kiematics Motion in Two Dimension & Vectors

 作者: physics   总分: 66分  得分: _____________

答题人: 游客未登录  开始时间: 22年07月20日 00:48  切换到: 整卷模式

标记此题
1#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which one of the followisa4/.elehypbl jb93s.dfr 3)vx1 u+kng is an example of a vector quantity?

参考答案:    

标记此题
2#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following operations will not changea rrsz5wh+w9 +y1vsc. a vector?

参考答案:    

标记此题
3#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Which of the following is an accurate statement:c0 7hw3-7m)r5l7exozlt j0e iehy 5z vgh :uy?

参考答案:    

标记此题
4#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The resultant of two vectors is t-kuv tpfk qg) 6b1; .o4j(uvbdg3pd6p he smallest when the angle between them is

参考答案:    

标记此题
5#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two displacement veclo6isxc p;93y :y6emvtors have magnitudes of 5.0 m and 7.0 m, respectively. When these two vectors are added, the magniti yp3; yvlxsc:eo696mude of the sum

参考答案:    

标记此题
6#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors, of magnitudes 20 and 50, are added. Which one of the fobz0h 5x w1t:k+i2vsiullowing is a possible answer fortu52 b0:hik1vi swzx+ the magnitude of the resultant?

参考答案:    

标记此题
7#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three forces, each hccsa ,:6gwka3e4rboz( n5 bx3aving a magnitude of 30 N, pull on an object in directions that a5na3( rgwzcc:eobb3 k6s ,4xare $120^{\circ}$ apart from each other. Make a statement concerning the resultant force.

参考答案:    

标记此题
8#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  In the diagram shown, the unknown vectoh h04t7okha t8r is


本题所包含的其它图片:

参考答案:    

标记此题
9#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Ignoring air resistance, the horizontal component of ats*ghq/ku j 3) projectile's velocity

参考答案:    

标记此题
10#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball is thrown with a velocity of 20 m/s at an aux) mot)2h0 vttnu0s1h7, c pzngle of 60e above the horizontal. What is the horizontal component of its instantaneous velocity at the exact top of its tr 2thvz0ttnc17mpho x s u0u)),ajectory?

参考答案:    

标记此题
11#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Ignoring air resistance, the horizontal component of a projectile0.2zdxtoj+y g8i vr 6c's accelerationt 6j 8y0r.cio v+g2dxz

参考答案:    

标记此题
12#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A soccer ball is kicked with a velocitpkhwf)en 1ao-08aemh c e yu42u2r(1 dy of 25 m/s at an angle of $45^{\circ}$ above the horizontal. What is the vertical component of its acceleration as it travels along its trajectory?

参考答案:    

标记此题
13#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the acceleration vector oar e d8xlu+ojala0z)h .3*w.of an object is directed anti-parallel to the velocity vect8.wlahajuo * ax r+).ozdel30or,

参考答案:    

标记此题
14#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If the acceleration of an o* lk *w/hap0v2n/aqwrbject is always directed perpendicular to its velocitnwl wa** phk/r/ 0qva2y,

参考答案:    

标记此题
15#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  At what angle should a water-gun be aimed in order for thje/il 3ec:2 k3dt4jva e water to land with the greatest horit: 3e2jedkai3/cj 4vlzontal range?

参考答案:    

标记此题
16#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An Olympic athlete throws a javelin at fou 3+;8jdt6a igh3ta hdur different angles above the horizontal, eadjt38dgi +u 3t hah6a;ch with the same speed: $30^{\circ}$, $40^{\circ}$, $60^{\circ}$, and $80^{\circ}$. Which two throws cause the traveling to land the same distance away?

参考答案:    

标记此题
17#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are throwing a ball for the798w:juqp q(qldfi ;fu 2;cue second time. If the ball leaves your hand with twice the velocity it had on your first throw, its horizontal range R (compared to your l uq: 9(8jfwuec7pqfu;2iq;d first serve) would be

参考答案:    

标记此题
18#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball is thrown at an original speed of 8.* hx+7j,hd8(h 0z5a b4m hqv yh4wougy0 m/s at an angle of $35^{\circ}$ above the horizontal. What is the speed of the ball when it returns to the same horizontal level?

参考答案:    

标记此题
19#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  When a football in a fi3ju3k e+fhgq3r ;g;(di b9/gy pm up:yeld goal attempt reaches its maximum height, how does its speed compare ygju(krg;gmhi up dq3;/3y:p3+b e9fto its initial speed?

参考答案:    

标记此题
20#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A stone is thrown horizoc i c :qdp,yf:qo g0gf45fom*la/-4hqntally from the top of a tower at the same instant a ball is dropped vertically. Which object is traveling fasterp ,f-/ ol*qofca5fi4ych gq0 mg4:dq: when it hits the level ground below?

参考答案:    

标记此题
21#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A bullet is fired horizontally, and at the same instant a seconvh yjzgt0w:*fa 056 es0i1wu a so6ry.d bullet is dropped from the same heiga6s zethr5yw y i1 u0vj6* gws.:af0o0ht. Ignore air resistance. Compare the times of fall of the two bullets.

参考答案:    

标记此题
22#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane flying horizontally at a spe(3gfg k)wmf, z w +aflvz hgosv-x48.-ed of 50.0 m/s and at an elevation of 160 m drops a package. Two seconds later it drops a second package. How far apart will the two pf3fz,l f8-v4vzmwkw.+sogx - a(gg )hackages land on the ground?

参考答案:    

标记此题
23#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A package of supplies is dropped from a plrjp:u g)p p0da.gfa ;x)0ao5gane, and one second later a second package is dropped. Neglecting air resistance, the distance betweeo dg ag)j g;pf)pu5 r:0xp.0aan the falling packages will

参考答案:    

标记此题
24#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A pilot drops a bomb from a plane flying hori:,gxb p2 q-ofqb(dn8bzontally at a constant speed. Neglecting air resistance, when the bo:8bngfpq-b 2(, bod qxmb hits the ground the horizontal location of the plane will

参考答案:    

标记此题
25#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The acceleration of gravity on the Moon is only one-sixthn 7oh3yl9fs4n /dbh( *j qd(wd heq9y0 of that on Earth. If y q 79*fb hehnnsq(ddwd yol (3h04j/9you hit a baseball on the Moon with the same effort (and at the speed and angle) that you would on Earth, the ball would land

参考答案:    

标记此题
26#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are traveling at 55 mi/h n-v.dnjv ) n zs j.re)u+,9:ojlznf4zh+ic3 xin the +x axis relative to a straight, level road and pass a car traveling at 459ih-)un, nne )3vjj ldz+o+ zr.s:. n4 cjvfzx mi/h. The relative velocity of your car to the other car is

参考答案:    

标记此题
27#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  You are trying to cross a river thal pf5hdlqcl( z2,p;c 3t flows due south with a strong current. You start out in your motorboat on the east bank desiring to reach the west bank directl2c(,q5d ;pf 3p clzlhly west from your starting point. You should head your motorboat

参考答案:    

标记此题
28#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Your motorboat can move at 30 km/h in still water. .oc5j l 4hrswn,m*u5h How much time will it take you to move 12 km downstream, in,r joh.w nh 5m4usl5c* a river flowing at 6.0 km/h?

参考答案:    

标记此题
29#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Vector A has magnitude 8.0 m at an angle of 30 degre 5-ru c+kb/ey4x2sws iwhkn,0es below the +x axis. The y component of A iss/5,k i-ucr nw+khsw4bxe 02y

参考答案:    

标记此题
30#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If a ball is thrown with a velocity n7 k,dahc pn12lno9*hi 10w7 dtvkk/xof 25 m/s at an angle of $37^{\circ}$ above the horizontal, what is the vertical component of the velocity?

参考答案:    

标记此题
31#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If you walk 6.0 km in a straight line in a direction north of east andk;u5cnil+. p; vqs qg*)gtws4* ye4) xnljd.b you end up 2.0 km north andcvg p ny;5 )n;q+l.gsbusi k q.4ljxd*e 4wt)* several kilometers east. How many degrees north of east have you walked?

参考答案:    

标记此题
32#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A butterfly moves with a speed of 12.0 m/s. The x cw8l6id vsazy+,nx (a(omponent of its velocity is 8.00 m/s. The angle between the direction of its lxzi (d+a8,a wn(v6sy motion and the x axis must be

参考答案:    

标记此题
33#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A 400-m tall tower casts a cgt456c k7nlz :3tc jy600-m long shadow over a level ground. At what angle is th3cct6jg n ylk 7:5c4tze Sun elevated above the horizon?

参考答案:    

标记此题
34#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors A and B ;hv.kcefi1*d, nc qmr u7y-q 9have components (0, 1) and (-1, 3), respectively. What are the components of kneu*h,fd. ;7cviq -q1 yc9mrthe sum of these two vectors?

参考答案:    

标记此题
35#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two vectors A and B have components (0, 1) uei.h 9 b66d a(z9 cly1yiy9mqand (-1, 3), respectively. What is magnyycbd9q i6ih( zy9 .1ea 6ml9uitude of the sum of these two vectors?

参考答案:    

标记此题
36#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Vector A = (1, 3). Vector B = (3, 0). Vector C = A + B . What is the magnit7 zb6spcs1)et/ )fql)t y+ ifiy(uxy0ud+)iyfy67s()0b q)flcx tpz1s t iey/ue of C ?

参考答案:    

标记此题
37#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A car travels 20 km West:gb qtmds3r bq-6fnxvmwx.l67/* o9y , then 20 km South. What is the magnitude of its displacemevr g6q m dxx m*t9qobn/ bfwl-y.7:6s3nt?

参考答案:    

标记此题
38#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three vectors, expressed in Cartesiygk 8:gsefwz8/sv(+ j5 so n1fan coordinates, are
S = (-3.5,+4.5)
T = (0,-6.5)
U = (+5.5,-2.5)
What is the magnitude of the resultant vector S + T + U ?

参考答案:    

标记此题
39#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Three vectors, express;z103kkkcslu7i xq e 8ed in Cartesian coordinates, are
S = (-3.5,+4.5)
T = (0,-6.5)
U = (+5.5,-2.5)
What is the angle of the resultant vector S + T + U measured from the positive x axis?

参考答案:    

标记此题
40#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  If vector A = (-3.0, -4.0) and vector B = (+3.0, -8.0), what is theq;k5-asny/ rz magnitude of vector C = A;q 5nrsk z-ay/ - B ?

参考答案:    

标记此题
41#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A runner runs halfway around a circular path of radius 10 m. , suvd; av.v4qnpy-qem -7j;u What is the displacement of the jogg svvq.-;,;adm4unjqu 7yvpe -er?

参考答案:    

标记此题
42#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two forces are acting on an objectwy4;1xxty ;bmrtb9fhqab /) 5 as shown in Fig. 3-1. What is the magnitude of the resultay1; wyaqrm;bfxtx 49bht b)5/nt force?


本题所包含的其它图片:

参考答案:    

标记此题
43#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  Two forces are acting on an object as shown in Fig. 3-uoyca+ic1 ; 7w1. What is the direction of the resultant force?i 7;c+awcoyu1


本题所包含的其它图片:

参考答案:    

标记此题
44#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Vector A is 5.5 cm long an1v eyk.19l0un 2atl;wizci;md points along the x axis. Vector B is 7.5 cm long and points at +30e to the negative x avlny e;z9 twmk 0a.i1il12uc;xis.
(a) Determine the x and y components of Vector A .
(b) Determine the x and y components of Vector B.
(c) Determine the sum of these two vectors in terms of components.
(d) Determine the sum of these two vectors in terms of magnitude and direction.
参考答案:    

标记此题
45#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
Vector A is 75.0 cm long ay/wvt6phr6 a-r-vyo8nd points at $30^{\circ}$ above the positive x axis. Vector B is 25.0 cm long
and points along the negative x axis. Vector C is 40.0 cm long and points at $45^{\circ}$ below the negative x axis.
(a) Determine the x and y components of Vector A .
(b) Determine the x and y components of Vector B .
(c) Determine the x and y components of Vector C .
(d) Determine the sum of these three vectors in terms of components.
(e) Determine the sum of these three vectors in terms of magnitude and direction.
参考答案:    

标记此题
46#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A stone is thrown horizontally with an initial speed of)a -ptj -pwu 77fdxu.z ,8rjvu 10 m/s from the edge of a cliff. A stop watch measures the stone's trajectory time from the top of the cliff to the bottom to be 4.3 s. What is the height of7xfwvpt-7drua-,p8 uu. zjj ) the cliff?

参考答案:    

标记此题
47#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A girl throws a rock horizontally, with a velocity of 1u 6;a c(6vl1mpnm zb vnba00x2;f3nkk0 m/s, from a bridge. It falls 20 m to the water below. How far does the rock travel horizontally before s ;n x 0pm(2unbnkb;z0cvva16f alm6k 3triking the water?

参考答案:    

标记此题
48#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A ball thrown horizontally from a point 24 m above the ground, strikes the groun6ntfi 4u6jz1;svg vv)d after traveling horizontally a distance of 18 m. With wha4j svv tuv6nz)f;g1 i6t speed was it thrown?

参考答案:    

标记此题
49#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jumper in the long-jump goes into the jump with a v4ndx7gt+-rb speed of 12 m/s at an angle ofxdv 4+tbn g-r7 $20^{\circ}$ above the horizontal. How long is the jumper in the air before returning to the Earth?

参考答案:    

标记此题
50#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A jumper in the long-jump goes into the jui ) 9 2f/x94 rlmsr1yhz r-iivw6t1kzdmp with a speed of 12 m/s at an angle of9rd i62 w z/xtm1-l)iv4kfrszy h 1ri9 $20^{\circ}$ above the horizontal. How far does the jumper jump?

参考答案:    

标记此题
51#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A projectile is launched with an initial velocity of 60.0 m/s c4 ;g:h7 sskhvat an angle of $30.0^{\circ}$ above the horizontal. How far does it travel?

参考答案:    

标记此题
52#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A projectile is launched wg/f*y t;dw(qmith an initial velocity of 60.0 m/s at an angle of $30.0^{\circ}$ above the horizontal. What is the maximum height reached by the projectile?

参考答案:    

标记此题
53#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A rifle bullet is fired at an apbc/ve js8sh 6bd);g4ngle of $30^{\circ}$ below the horizontal with an initial velocity of 800 m/s from the top of a cliff 80 m high. How far from the base of the cliff does it strike the level ground below?

参考答案:    

标记此题
54#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A projectile is shot horizontally at 23.4 m/s from the roof of a buildin ut4h .o69gbcoj rjd07g 55.0 m talcdjg0ro76t4jouh . 9b l.
(a) Determine the time necessary for the projectile to reach the ground below.
(b) Determine the distance from the base of the building that the projectile lands.
(c) Determine the horizontal and vertical components of the velocity just before the projectile reaches the ground.
参考答案:    

标记此题
55#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A projectile is fired from ground level with an initia x1+ 2b ,xld6z:hxfswvl speed of 55.6 m/s at an ang bxzv1sl, d2wx6x :hf+le of $41.2^{\circ}$ above the horizontal.
(a) Determine the time necessary for the projectile to reach its maximum height.
(b) Determine the maximum height reached by the projectile.
(c) Determine the horizontal and vertical components of the velocity vector at the maximum height.
(d) Determine the horizontal and vertical components of the acceleration vector at the maximum height.
参考答案:    

标记此题
56#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  On a calm day (no wind), you can run a 1500-m race at kysx ,.k-k-lr a velocity of 4.0 m/s. If you ran the same race on a day when you had a constant headwind which slows your speed by 2.0 m/s, the time it would take youl . srkkx-k,-y to finish would be

参考答案:    

标记此题
57#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane has an air speed of 200 m/s due North, and is in a wind 9 :aezu oh5o6o ,ggo:yhr4z h1of 50.0 m/s to the West. The plane's speed relu4:5 o 9 agge6,ho1o h:zhyrzoative to the ground is

参考答案:    

标记此题
58#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A plane is flying due Soutiu 9os ;fo*s:vpv,+ji2 uc7nhh ($270^{\circ}$) at 500 km/h. A wind blows from East to West ($180^{\circ}$) at 45.0 km/h. Find the plane's velocity with respect to the ground.

参考答案:    

标记此题
59#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  An airplane with a speed of 120 km/h is headeqljs 1/bl af/r pk.2-( ma;dk6pw o7ltd $30.0^{\circ}$ east of north in a wind blowing due west at 30.0 km/h. What is the speed of the plane relative to the ground?

参考答案:    

标记此题
60#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A fighter plane moving 200 m/s horizontally fires a projectile with speed 50.0 m.8nob56 1jg nmw,ucbm/s in a b5jw1c, m mn86u .nbogforward direction $30.0^{\circ}$ below the horizontal. What is the speed of the projectile with respect to a stationary observer on the ground?

参考答案:    

标记此题
61#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A boat, whose speed in still water is 8.0 m/s, io 3bch0iw,u +qs directed across a river with a current of 6.0 m/s. What is the speed of the boat as itu, 0+q whbio3c crosses the river?

参考答案:    

标记此题
62#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The driver of a motorboat that can move at nik gvfj26 le:6a/w;a10 m/s in still water wishes to travel directly across a river 1.6 km wide in which the current flows at 5.0 m:evk 2agij6/n lw6fa;/s. How long will it take to cross the river?

参考答案:    

标记此题
63#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  The driver of a motorboat that can move at 10 m/s in still watee c)x vf:ite48r wishes to travel directly across a narrow strait i 4 e)iecftxv8:n which the current flows at 5.0 m/s. At what angle upstream should the driver head the boat?

参考答案:    

标记此题
64#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A swimmer heading directly across a river 20mhjdo+qp4 1 2*uemjw*0 m wide reaches the opposite bank in 6 min4hj qm o*+dwj*2ep1mu 40 s. She is swept downstream 480 m. How fast can she swim in still water?

参考答案:    

标记此题
65#
 
单选题 ( 1.0 分) 切至整卷模式 搜藏此题  
  A swimmer heading directly across a river 201gy dw2:.q:kf va9l2n io -moa0 m wide reaches the opposite bank in 6 min 40 s. She -o :yof.wkmd:lvaq229a i1gnis swept downstream 480 m. What is the speed of the current?

参考答案:    

标记此题
66#
 
问答题 ( 1.0 分) 切至整卷模式 搜藏此题  
A boat, whose speed in still water is 1.75 m/s, must aim upstreau7:t 1f o31p91xrmw6 tl udo kdv*iat/m at an angle oflt okot :9/3 d r1 u7*ftmpud1ixvw16a $26.3^{\circ}$ (with respect to a line perpendicular to the shore) in order to travel directly across the stream.
(a) Determine the speed of the current.
(b) Determine the resultant speed of the boat with respect to the shore.
参考答案:    

总分:66分 及格:39.6分 时间:不限时
未答题: 已答题:0 答错题:
当前第 题,此次习题练习共有 66 道题
本平台(https://autodiscover.51fly.win/)支持练习,作业与考试(自动评分)三种模式,群组成绩统计排序导出,题目动态变量实现同卷千人千题
如果您对本系统感兴趣,想加入我们或者想进行任何形式的合作,请加微信 skysky1258

浏览记录|手机版视频|手机版试卷|使用帮助|51fly国际课程 (https://51fly.win)

GMT+8, 2026-4-18 06:29 , Processed in 1.199548 second(s), 162 queries , Redis On.