a) We want to calculate:
We can write the last equation in the following form:
Where we have used the laws of exponents. Now we can replace the terms inside the parenthesis with the equation of the statement and find that:
Where in the last step we just multiplied 9 with 59049.
b) We consider:
We know that: 81 = 9*9 = 9^2 , so using that, and the laws of exponents we conclude that:
So: