Hypothesis testing is basically testing the results of a experiment to see weather your results are valid or not.
Answer:within the focal length of the lens, provided the focal length is shorter than the near point distance.
Explanation:Hope it helps
Answer: The height of the pile increasing is increasing at 
Explanation:
Given
Rate at which gravel is being dumped , 
=>Rate of increase of volume of cone=
If height of the cone at any instant is h then the diameter of cone is also h
Volume of cone , 
Now differentiate both sides w.r.t time(t)

Therefore at h = 9 ft

=>
Thus the height of the pile increasing is increasing at 
Molarity is a concentration unit, defined to be the number of moles of solute divided by the number of liters of solution.
It protects us by keeping ultraviolet out and make sure everything lives