气体膨胀对外界做功100J,同时从外界吸收了120J的热量,它的内能的变化可能是[ ]
A.减小20J
B.增大20J
C.减小220J
D.增大220J
答案:B
列竖式计算(带“△”的要验算)
△721÷7=
△247÷3=
37×62=
1.6+29.7=
Look, _____ fashionable clothes is she wearing that all the eyes are fixed on her![ ]
A. so
B. such
C. how
D. what