Answer:
B) how steep the slope is
Explanation:
Because you have to know how is the influence of the steep of the slope in the time that a ball reaches the bottom. The steep of the slope is the variable that you would have to change in an experiment.
I hope this is useful for you
regards
Answer:
this situation would not be physically possible
Answer:

Explanation:
c = Speed of wave
= Density of medium
A = Area
= Frequency

Intensity of sound is given by

So,

We get

The ratio is 
The principle of a lever is when two equal forces act in opposite directions and ultimately come to a state of equilibrium if distanced properly
i hope that helps?^
Velocity = displacement/time
I hope i helped you <33