_______ me carefully, boys and girls. Can you _______ me? A. Listen to; hear B. Hear; listen to C. Hear; hear D. Listen to; hear from 答案:A如图所示,U形管左端管口处有一小气球,管内装有水银,当往右管内再注入水银时,气球将鼓得更大,假设封闭的气体与外界无热交换,则在注入水银时( )
A.封闭气体的体积将增大 B.封闭气体的压强将增大
C.封闭气体的内能将增大 D.封闭气体的密度将增大