Please explain the steps to completing this problem

Rensing Ltd. estimates sales for the second quarter of 2017 will be as follows.

Month Units

April 2,590

May 2,450

June 2,350

The target ending inventory of finished products is as follows.

March 31 2,040

April 30 2,250

May 31 2,110

June 30 2,370

2 units of material are required for each unit of finished product. Production for July is estimated at 2,800 units to start building inventory for the fall sales period. Rensing's policy is to have an inventory of raw materials at the end of each month equal to 70% of the following month's production requirements.

Raw materials are expected to cost $5 per unit throughout the period.

How do I calculate the May raw materials purchases in dollars.