汽体塔顶部压力变化影响因素有哪些？

阅读理解。

      John is traveling by train. He is very hungry. The train stops at a small station. He wants to buy one

cake to eat very much., but it's raining hard. He wants someone to help him. A little boy is coming over

to him. John asks him to buy cakes for him. He gives the little boy one yuan and says, "Go and buy two

cakes with the money. One cake is for me, the other is for you. Can you help me?"

      The little boy is very happy and runs over to buy cakes in the rain. A few minutes later the boy comes

back and says to John," I'm sorry. I'm eating the last cake. It's delicious. Thank you very much. Here is

your fifty fen."

1. John is traveling _______.

A. by plane

B. by train

C. by bus

2. John wants to eat _______.

A. one cake

B. two cakes

C. two more cakes

3. _______ helps John to buy cakes.

A. A little boy

B. A little girl

C. A man

4. The little boy can't buy two cakes because _______.

A. there is only one cake left.

B. he doesn't like to buy two

C. John wants him to buy one

5. John is very _______.

A. happy

B. hungry

C. angry

心的生理特点是什么？（）

A.为主宰

B.主治节

C.主温运

D.主运化

E.主血脉

钢轨气压焊正火后的接头温度降至（）℃以下才可拆除轨下垫木。

A.900

B.800

C.700

D.500

甲状腺素对下列哪个器官的发育最为重要

A．肝和脑
B．脑和心
C．肝和肾
D．肾和心
E．骨和脑

某挡土墙，高5m，墙背直立、光滑，填土面水平。填土的物理力学性质指标为：c=10kPa，=20°，γ=19kN/m³。则作用在挡土墙上的主动土压力及其作用点位置为（）。

A．51.4kN/m，1.14m

B．58.5kN/m，1.14m

C．51.4kN/m，1.34m

D．58.5kN/m，1.34m