Someone please help fast!!

Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

Find the distance between the pair of points a(-1,8) and b(-8,4)

Answer asap! show all work! find the number of complex roots, the possible number of real roots and the possible rational roots of the polynomial function. then, solve for all roots. x^3 + 2x^2 + 3x + 6 = 0