народ помогите пожалуйста,первый пункт знаю как решать а вот 2 и 3..

[Равиль94]

1.At 1 May 20X5 the company had 700 engines in inventory, valued at $190 each. During the year ended 30 April 20X6 the following transactions took place:
20X5
1 June Sold 200 engines for $64,000
1 July Purchased 500 engines at $220 each
1 November Sold 400 engines for $160,000
20X6
1 January Purchased 150 engines at $ 230 each
1 February Purchased 300 engines at $230 each
15 April Sold 250 engines for $125,000

a)Calculate Revenue (3 points)
b)Calculate COGS (3 points)
c)Calculate the value of the company’s closing inventory of engines (4 Points)
at 30 April 20X6?