ALGORITHM Mystery(n) //Input: A nonnegative integer n SO for i 1 to n do SS+i*i return S Pick the summation formula that represents the running time for the algorithm. n T(n) = i = 1 n T(n)= n2 i = 1 n T(n) = 21 i = 1 n T(n) = ogn i = 1 ALGORITHM Mystery(n) l/Input: A nonnegative integer n S=0 for i = 1 to n do SS+i *i return S a. What does this algorithm compute? b. What is its basic operation? C. How many times is the basic operation executed