汽车以20m/s的速度做匀速直线运动,见前面有障碍物立即刹车,刹车后加速度大小为

题型:选择题

问题:

汽车以20m/s的速度做匀速直线运动,见前面有障碍物立即刹车,刹车后加速度大小为5m/s2,则汽车刹车后2s内及刹车后5s内通过的位移之比为(  )

A.1:9

B.1:3

C.5:13

D.3:4

考点:匀变速直线运动的速度与时间的关系匀变速直线运动的位移与时间的关系
题型:选择题

阅读理解。根据短文内容给下列的句子排序。

      Do you know how to plant a peach tree? Let me tell you. First, put some soil in a pot. Then, put a peach

seed in the soil. Water the seed. Put it in the sun. When it's dry again, water it. You can see the sprout in a

few weeks. Don't forget to put it in the sun every day. Wait. You can see a big plant in several months. When

can it grow peaches? Wait. It will take a long time.

( ) Don't forget to put the pot in the sun every day.

( ) When the soil is dry again, water it.

( ) Wait for the peach tree to grow.

( ) First, put a peach seed in the soil.

( ) Then, water the seed and put it in the sun.

题型:选择题

诊断疾病时,既要重视病人整体的病理联系,还要将病人与其所处环境结合起来综合判断病情的方法,属()

A.四诊合参

B.病证结合

C.整体审察

D.见微知著

E.司外揣内

题型:选择题

GPS点位置选择要求中,当GPS点间需要通视时,应在附近设方位点,两者之间的距离(),其观测精度应与GPS点相同。

A.不宜小于500m

B.不宜小于100m

C.不宜大于300m

D.不宜小于300m

题型:选择题

中国有句古话:“尧为匹夫,不能治三人;纣为帝王,足以乱天下。”意思是说:即使像尧那样贤明的人,假如他是个普通老百姓,手里没有权力,也管不了几个人,干不了什么太大的好事;但是像商纣王这样品行不端的人,一旦当了帝王,手中有了无限的权力,就可以把天下搞得大乱。这主要说明 [ ]

A、权力与责任总是相伴相依

B、权力是把双刃剑

C、要发挥民主、法制对权力的制约

D、要建立和完善对权力的监督体系

题型:选择题

茶碱的有效血药浓度范围正确的是()

A.0-10μg/ml

B.15-30μg/ml

C.5-10μg/ml

D.10-20μg/ml

E.5-15μg/ml

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