已知一条弧的长是2π厘米,弧的半径是8厘米,则这条弧所对的圆心角是______度.
设所对的圆心角是n度,根据题意得:8nπ180=2π,
解得:n=45,
故答案是:45.
—The classroom is clean it was yesterday.
—Sorry, I forgot to clean it.
A.as, as
B.so, as
C.not as, as
D.more, than
正态化选择