Answer: It takes the stone 7seconds in air and 5seconds in water
Explanation: complete question: How long did the stone fall in air and how long did it fall in the water?
total distance = sum of velocity * time for both legs of the journey;
let the time taken in air be t
hence time taken in water is 12-t
127 = 16*t + 3(12-t)
127 = 16t + 36 - 3t
127 - 36 = 16t - 3t
91 = 13t
t = 91/13 = 7 seconds
Hence time taken in air = 7 seconds
time taken in water is 12 - 7 = 5 seconds
The efficiency of the process is 42%
From the question given above, the following data were obtained:
Useful energy = 250 watt
Wasteful energy = 600 watt
<h3>Efficiency =? </h3>
The efficiency of the process can be obtained as illustrated below:

<h3>Efficiency = 42%</h3>
Therefore, the efficiency of the process is 42%
Learn more: brainly.com/question/2300041
They hibernate to a point, they build dens when it gets cold to stay out of the freezing cold but don't sleep all winter
I think the correct answer from the choices listed above is the third option. It is the difference in electrical potential that causes the electric charges to flow from one end of the battery to the other. Hope this answers the question. Have a nice day.