请教一道天山题

dongziyuan

 if p is the product of the integers from 1 to 30,inclusive,what is the greatest integer k for which 3^{k  _{is a factor of p?}}

_^A.10

_^B.12

_^C.14

_^D.16

_^E.18

shawlen

试解：1到30，有3（1到10）的倍数10个，9的倍数3个，27的倍数1个，

K=10-3+2*2+3=14