对以下程序段的描述,正确的是( )。 x= -1; do x=x*x; 发布时间:2018-01-02 07:55 │ 来源:www.tikuol.com 题型:单项选择题 问题: 对以下程序段的描述,正确的是( )。 x= -1; do x=x*x; while(!x);A.是死循环B.循环执行两次C.循环执行一次D.有语法错误
题型:单项选择题 完形填空。 It is 1 in Qingdao. It is very hot here. Now, there are many people 2 vacation. They go to the beach and have 3 good time there. Today is 4 . It is not very hot. On the beach, a lot of people 5 to their friends 6 looking at the beautiful sea. Some of them are 7 . Others are taking 8 . Can you find 9 ? I'm the boy in blue shorts. I'm going to dive. It's 10 .( ) 1. A. August ( ) 2. A. in ( ) 3. A. / ( ) 4. A. winds ( ) 5. A. is talking ( ) 6. A. to ( ) 7. A. swim ( ) 8. A. photos ( ) 9. A. I ( ) 10. A. hot B. December B. on B. an B. wind B. are talkingB. but B. swims B. photoes B. me B. warm C. March C. at C. a C. winding C. is sellingC. and C. swimming C. phones C. my C. cold D. January D. with D. the D. windy D. are sellingD. because D. swam D. potatoes D. mine D. cool 查看答案
题型:单项选择题 列式计算(1)4.68除以1.8的商,比6.5乘1.2的积少多少?(2)7.84的1.4倍再除以3.92,商是多少?(3)某数的4倍与这个数的三倍的和是9.8,求这个数?(4)5与9的积减去X的3倍是2.1,求X. 查看答案
题型:单项选择题 如图所示,两根质量均为0.1 kg完全相同的导体棒a、b,用绝缘轻杆相连置于由金属导轨PQ、MN架设的斜面上。已知斜面倾角θ为53°,a、b导体棒的间距是PQ、MN导轨间间距的一半,导轨间分界线OO′以下有方向垂直斜面向上的匀强磁场。当a、b导体棒沿导轨下滑时,其下滑速度v与时间的关系图像如下图所示。若a、b导体棒接入电路的电阻均为1Ω,其它电阻不计,取g=10 m/s2,sin53°=0.8,cos53°=0.6,试求:(1)PQ、MN导轨的间距d;(2)a、b导体棒与导轨间的动摩擦因数;(3)匀强磁场的磁感应强度。 查看答案