A:2ab和3ab
B:2a2b和3ab2
C:2ab和2a2b2
D:2a3和﹣2a3
Something is wrong with my computer. I'll have it______.
爷爷的老式钟一点也不准,它的时针与分针每隔61+411分钟重合一次,则这只时钟每天快或慢多少分钟?( )