In how many different number of ways 2 boys and 2 girls can sit on a bench?  Choose the correct choice from the following answers:	A) 720	B) 730	C) 740	D) 750	E) 24
npn = n!   4p4 =4 × 3 × 2 × 1 = 24   24
<result>E</result>
In how many different number of ways 2 boys and 2 girls can sit on a bench?