During a regular respiratory cycle, the volume of air in liters in the human lungs can be described by the function V(t) = 0.173t + 0.152t2 - 0.035t3, where t is the time in seconds.
a. Estimate the real zeros of the function by graphing.
b. About how long does a regular respiratory cycle last?
c. Estimates the time in seconds from the beginning of this respiratory cycle for the lungs to fill to
their maximum volume of air.