已知10x=m,10y=n,则102x+3y等于 [ ]
A.2m+3n
B.m2+n2
C.6mn
D.m2n3
答案:D
_______ late the next morning, Bob turned off the alarm.
A.To sleep
B.Sleeping
C.Sleep
D.Having slept
我国疆域北起漠河以北的乌苏里江江心,南到曾母暗沙。( )