9.43 units
for some reason the answer has to be 20 characters long
I believe x = 18
Let me know if you need an explanation
Hope this helps!
Step-by-step explanation:

<h2>
The stone fall in air for 7 seconds and fall in water for 5 seconds.</h2>
Step-by-step explanation:
Total distance to sea bed = 127 m
Let the distance traveled in air be s.
Distance traveled in water = 127 - s
Average velocity in air = 16 m/s
Average velocity in water = 3 m/s
Distance traveled in air = Average velocity in air x Time in air
s = 16 x t₁

Distance traveled in water = Average velocity in water x Time in water
127-s = 3 x t₂

We have total time is 12 seconds
That is
t₁ + t₂ = 12

We have
s = 16 x t₁
112 = 16 x t₁
t₁ = 7 s
t₁ + t₂ = 12
7 + t₂ = 12
t₂ = 5 s
The stone fall in air for 7 seconds and fall in water for 5 seconds.
Answer:Read below 18
Step-by-step explanation: if a number by alphabet its 18 but if not I would need to see more please respond