here given 'd' that is distance is 168 feet. we need to find seconds that is 't'.
from the given formula,
⇒ d=16 t²
⇒ [tex] \frac{d}{16} [/tex] = t²
⇒ t²= [tex] \frac{168}{16} [/tex]
⇒ t²= 10.5
⇒ t=[tex] \sqrt{10.5} [/tex]
⇒ t=3.24
thus the seconds required is 3.24 seconds
