I need points so I can ask my question hope you get your answer
Answer:
The choice third ; a=9 , c= 18
Step-by-step explanation:


The height is increasing at the rate of (6/5π) ft/min.
It is given that Gravel is being dumped from a conveyor belt at a rate of 40 ft3/min. Also, its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal.
For this, we need to find the volume of a cone. Volume is a scalar quantity expressing the amount of three-dimensional space enclosed by a closed surface.
The volume of a cone is - V=1/3hπr²
Learn more about integers here: brainly.com/question/20521181
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