下面各式积的末尾各有几个0?)n/o'~9_3P'@;p'p,y
4000×70的积的末尾有'N*I-O8D个0。)n/o'~9_3P'@;p'p,y
1200×50的积的末尾有7w7U;V8v's0d:K2|9r.~)L4@)E个0。)n/o'~9_3P'@;p'p,y