Mutpliy please I need to finish this:)

Andy is making a design using ice cream sticks that are 4 and 1/2 in long he wants this long side of his designed to be no longer than 24 inches what is the greatest number of sticks that any can use on his long side of his design

Bring the fraction a/a-4 to a denominator of 16-a^2

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83