—Would you like me to carry this box for you?  

—_________.I can manage it myself.

A．No, thanks

B．It’s a pleasure

C．That would be nice

D．Yes, please

如图所示，汽油机的压缩冲程中，进气门和排气门都关闭，活塞依靠旋转的惯性上运动，燃料混合气体被压缩，温度升高，活塞的_______ 能，转化为气体的________ 能。