3. (20p). Estimate the running times, in terms of n, of the following three programs. You should give tight bounds of the form (f(n)) with f as simplified as possible. Justify your answers. (You can assume that arithmetic operations take time in (1), no matter the size of the operands. Recall that the scope of language constructs is determined by indentation, so in (c), k k 3 is the while loop but not of the for loop.) part of for k 1 to n *n for k 1 to n * n while k