The height of a helicopter above the ground is given by h 5 3.00t3, where h is in meters and t is in seconds. At t 5 2.00 s, the helicopter releases a small mailbag. How long after its release does the mailbag reach the ground

Explanation:

The height of the helicopter is given by this function:

The height at is:

The mailbag experiments a free fall, whose equation is:

Time required before the mailbag reaches the ground is:

The roots of the second-order polynomial are:

Only the first root offers an physically reasonable solution. Then, the needed time is:

d) physical means can be used to separate the components of air.