Answer:

Explanation:
specific gravity of oil is 

we know that
change in pressure for oil is given as

here density and h is for oil

change in pressure for WATER is given as

here density is for water and h is for water

pressure change due to both is given as


Answer:
for students to do nothing
Explanation:
because doing nothing is not a course goal
(1)
Cheetah speed: 
Its position at time t is given by
(1)
Gazelle speed: 
the gazelle starts S0=96.8 m ahead, therefore its position at time t is given by
(2)
The cheetah reaches the gazelle when
. Therefore, equalizing (1) and (2) and solving for t, we find the time the cheetah needs to catch the gazelle:



(2) To solve the problem, we have to calculate the distance that the two animals can cover in t=7.5 s.
Cheetah: 
Gazelle: 
So, the gazelle should be ahead of the cheetah of at least
