Simplify the following, giving your answer with a positive index: $2^2\times2^2$22×22

Simplify the following, giving your answer in index form: $3^9\times3^{10}$39×310.

We want to simplify the expression $a^2\times a^3$a2×a3.

What term should go in the space to make the statement true?

$a^3\times?=a^7$a3×?=a7