Given:
Time of travelling is, 14 hours.
Travelled height is 140 feet.
The objective is to find the height of the submarine after 5 hours.
Since, it is given that the submarine is descending at a constant rate.
Then, the constant speed can be calculated as,
[tex]\begin{gathered} \text{Speed}=\frac{Dis\tan ce}{Time} \\ s=\frac{140}{14} \\ s=10\text{ ft/hr} \end{gathered}[/tex]Now, the height after 5 hours can be calculated as,
[tex]\begin{gathered} s=\frac{Dis\tan ce}{Time} \\ \text{d}=s\times t \\ d=10\times5 \\ d=50\text{ ft.} \end{gathered}[/tex]Hence, the height of the submarine in downwards after 5 hours is 50 ft.
