this is for math please answer ASAP ONLY ANSWER NO EXPLANTION. THANK YOU

21. DETAILS MYNOTES l ASKYOURTEACHER Suppose a person travels at a rate of 5 ft/hr toward the foot of a street lamp pole 63 ft high. The height of the person is 5.9 ft. At what rate is the distance from the head of the person to the top of the street lamp changing when 82 ft from the bottom of the street lamp? Note: Round your answer to 4 decimal places. 0 3.8281 ft/hr O -4 ft/hr O 0.243? ft/hr 0 4.1032 ft/hr 0 none of the other answers 0 3.9649 ft/hr O -0.2437 ft/hr Q 0 ft/hr 18. DETAILS Differentiable Function. If a differentiable function f(x) satisfies f(-3) = f(3) then there exists a c in (-3,3) with Of (c ) = 0 Of" ( c ) > 0 Of ( c ) > 0 Of" ( c ) 019. DETAILS MY N Flight of a Rocket. Suppose the altitude (in metres) of a rocket t seconds into flight is given by f(t) = -2+3 + 27+2 - 120t + 84 The interval where f(t) is concave up is O -00, 2 O (4, 5) O 9 2 O (-00, 4) U (5, 00 ) O (-00, 00) O none of the other answers\f