Riddles

i have some riddles :
what is the difference
beetween a mosquito
and a fly ???

i had a difficulty doing my homework
canyou help me ? ... 2x2x2x2x2x2x2x
5x5x5x5x6x6x7x7x8x9x9x6x+2+3x0+5+5x3=???

if i shoot 1/13 birds how
many birds are left ???

if i buy a jeans for 2.500.000
and get a discount 15 % and pay
3.000.000 how much change will i get ???

how can you put a mammoth in the refrigerator ???

if you know the answers write it on the comment part below
pls............