The volume would be 3.6cm4th power because 2cm x 0.09m x 20mm, you have to combine multiplication rules so you have to multiply the 2 x 0.0.09 x 20 and you would get 3.6cmxMxMxM, then you have to add the exponent if the term doesn't have one so it would be 3.6cm1 x m1 x m1 x m1. when you gather it, the sum would be 3.6cmxM1+1+1+1. the total answer would be 3.6cm4th power.