Suppose that Joshua spends 10 hours per day picking fruit. He can pick 1 kg of apples per hour and 1 kg of cherries every 2.5 hours.

B) At his local farmer’s market, Joshua can buy or sell as much fruit as he wants at a price of $4/kg for apples and $8/kg for cherries. If Joshua only wanted to consume apples, how many of each fruit should Joshua pick?
C)If, instead, Joshua only wanted to consume cherries, how many of each fruit should Joshua pick? What is the greatest amount of cherries, Joshua can consume?
d)At what prices would Joshua be willing to pick both types of fruit

im kind of stuck on these questions can someone explain how to do them