When you multiply numbers with the same base and exponents, you just add the exponents together. In the case of the first question:
[tex]11^{2}[/tex] * [tex]11^{7}[/tex] = [tex]11^{9}[/tex]
When dividing, subtract the exponents instead, and when there's an exponent outside the parentheses the way it is on the 3rd question, multiply them together.
Hope this helps! :)
