Which math problem is being modeled on the number line

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie

Marquise has 200 meters of fencing to build a rectangular garden. the garden's area (in square meters) as a function of the garden's width w w (in meters) is modeled by: a ( w ) = − w 2 + 1 0 0 w a(w)=−w 2 +100w what side width will produce the maximum garden area? meters

Layla answer 21 of the 25 questions on his history test correctly.what decimal represents the fraction of problem he answer incorrectly.