3. (18p). 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, this will involve expressing each running time as a sun. (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), kk2 is part of the while loop but not of the for loop.) 20 for k 1 to n *n 20 for k 1 to n * n while k<>