Question $4$

$1$ pts

FFS$4.$ For a ball thrown stra$$gh down at $20\frac{m}{s},$ how much speed downward does it have $3$ seconds later? Assume the acceleration of gravity is $10\frac{m}{s}$ per second for this problem.

$50\frac{m}{s}$

$30\frac{m}{s}$

$70$ m$/$s

$20$ m$/$s