Given the depth vs. clock time function y = f(t) = .02 t² + -2.62 t + 99, with depth in cm when clock time is in seconds, find the clock time when water depth is 86.19499 cm. Using the same function determine the depth at clock time t = 13 sec. Find t such that f(t) = 64.19499. Find f(t) when t = 31.