Please explain the answer and provide the equations needed to solve the question.

1. Me Inc. has an annual net income of $20 million, revenue of $60 million and cost of goods sold of $20 million. If the balance sheet amounts show $2.3 million in average inventory and $500,000 of property, plant & equipment, what is the Inventory turnover?

I just wasted a question by asking the question below. I got back an answer but it was very poorly explained. I am really trying to understand the breakdown of this question and the equations to solve it. Can someone please answer than question as well as the one above?

2. Sam buys fuel for his construction vehicles from the local distributer. He uses 8,500 gallons each quarter (every three months). The local distributor charges him $20.50 per order when he orders and it costs him $9.00 per gallon per year to store the gas at his farm. The distributer can arrive within an hour of his order and we have a 250 gallon tank he can fill. From a logical and reasonable standpoint, how much fuel should Sam order when he calls the distributer?

Me Inc. Annual Report Annual Net Income $20,000,000 Revenue $60,000,000 COGS $20*1000000 $2.3*1000000 Average Inventory Property, Plant, & Equipment $500,000