what is the mathematical LP formulation for this problem?

Reef's Petroleom produces three brands of oils: Regular, Multigrade, and Supreme. Each brand of oil is composed of one or more of four crude stocks, each having a different viscosity index. The relevant data concerning the crude stocks are: Each brand of oil must meet a minimum standard for viscosity index, and each brand thus sells at a different price. The relevant data concerning the three brands of oil are: Determine an optimal production plan for a single day, assuming that all oil produced during this day can be either sold or stored at negligible cost and that the daily demands are to be met precisely