Sent a picture of the solution to the problem (s).
You have to convert 50 feet to inches, so you take 50 times 12 and get 600. Then, you take 600/75 to get the number of rotations. Your final answer shold be 8 rotations.
The sum of the first n odd numbers is n squared! So, the short answer is that the sum of the first 70 odd numbers is 70 squared, i.e. 4900.
Allow me to prove the result: odd numbers come in the form 2n-1, because 2n is always even, and the number immediately before an even number is always odd.
So, if we sum the first N odd numbers, we have

The first sum is the sum of all integers from 1 to N, which is N(N+1)/2. We want twice this sum, so we have

The second sum is simply the sum of N ones:

So, the final result is

which ends the proof.
since the equation is c=9.5t, Sanjay paid c=9.5 x 14 shirts he bought. which =$133