In 2012, James Cameron descended to the bottom of Challenger Deep in the Marianas Trench; the deepest point in the ocean. The vessel he rode in was called the DeepSea Challenger.

Challenger Deep is
35
,
814
35,814​ feet deep at its lowest point.

a) DeepSea Challenger's descent was a change in depth of
−
4
−4​ feet per second. We can use the equation
�
=
−
4

y=−4x​ to model this relationship, where

y​ is the depth and

x​ is the time in seconds that have passed. How many seconds does this model suggest it would take for DeepSea Challenger to reach the bottom?