There's yet another one if you understand this Tell me how you got the answer cause I don't understand this

At a sand and gravel plant, sand is falling off a conveyor and onto a conical pile at a rate of 16 cubic feet per minute. the diameter of the base of the cone is approximately three times the altitude. at what rate is the height of the pile changing when the pile is 12 feet high? (hint: the formula for the volume of a cone is v = 1 3 πr2h.)

If myesha works overtime, she gets paid "time and a half" for every hour she works. in other words, for every hour over 40 hours myesha works each week, she gets her hourly pay plus half her hourly pay. what is myesha's pay per hour when she works overtime?

At store a, erasers are sold individually. the cost y of x erasers is represented by the equation y=0.75x. the costs of erasers at store b are shown in the graph.