Answer:a
Explanation:
We have to lift the load two loads up one story, so energy required is
let m be the mass of each load and h is the height of each story
Energy 
Here energy gained is the potential energy which depends upon the datum(floor).
For lifting one load up one story
Energy required
thus 
is half of 
So option a is correct
Answer:
The atomic nucleus is the small, dense region consisting of protons and [[]]s at the center of an atom
Explanation:
Answer:
24mph
Explanation:
it really depends how high but the average speed for that quick will be atleast 24mph if not try 42mph if it is wrong
Answer:
A force is a push or pull upon an object resulting from the objects interaction with another object
The statement "Good locations for turbines are limited" describes a drawback to wind energy.
Answer: Option B
<u>Explanation:</u>
Wind energy is one of the most useful and efficient renewable energy sources. But nothing is ideal in this universe and the same thing applies for wind energy also. The generation of electricity from wind energy requires setting up of turbines.
And these turbines can be set up in plane areas which is free from any disturbance except wind flow. In open area and flat plane surface only the turbines can rotate freely with the effect of wind.
But regions where the wind flow is minimum due to snow formation like the northern region of earth, the turbines cannot be set up there. So the locations for setting up of turbines are limited for good outcome in wind energy. This is one of the drawback of wind energy.
