Can someone correct these for me please.

Problem #68
Science and medicine. Find the time required for an object to fall to the ground from a building that is 1400 ft high. Using the formula t=(1)/(4)radical(s).

My answer: 9 minutes and 35 sec.

Problem #2

Use Property 1 to simplify each of the following radical expressions. Assume that all variables represent positive real numbers.

radical 50

My answer: 5radical(2)

Problem #24

radical (72x^3)

MY answer: (6x) radical (2x)

#2 and #24 look ok.
If your answer for #68 is 9.35 minutes on the calculator, that is NOT 9 minutes and 35 seconds. It is 9 and 35/100 of another minute or 0.35 x 60 = 21 seconds.