Answer:
Incomplete question
This is the complete question
A stone falls from the top of a cliff into the ocean.
In the air, it had an average speed of 16 m/s. In the water, it had an average speed of 3 m/s before hitting the seabed. The total distance from the top of the cliff to the seabed is 127 meters, and the stone's entire fall took 12 seconds.
How long did the stone fall in air and how long did it fall in the water?
Explanation:
The stone speed in air Sa =16m/s
The stone speed in water Sw=3m/s
Total distance travelled is 127m
Total time taken is 12 sec
Let time in air be ta
Tune in water be tw
Therefore
Total time =ta +tw
12=ta+tw. ,Equation 1
ta=12-tw. ,Equation 2
Also
Speed is given as
Speed = distance /time
Distance =speed × time
So, total distance = distance traveled in air + distance travelled in water
127= Sa×ta + Sw×tw
127=16ta+3tw. , Equation 3
Substitute equation 2 into. 3
127=16(12-tw)+3tw
127=192-16tw+3tw
127-192=-13tw
-65=-13tw
tw=-65/-13
tw=5 seconds
Also from equation 2
ta=12-tw
ta=12-5
ta=7 seconds
The stone spent 7 seconds in air and spent 5 seconds in water before getting to the seabeds