The Valley Company is a merchandising firm that sells a single product. The

company's revenues and expenses for the last three months are presented

below:

VALLEY COMPANY

Comparative Income Statement for the Second Quarter

Required:

a$.$ Determine which expenses are mixed and, by use of the high$-$low method,

separate each mixed expense into its variable and fixed components. State the

cost formula for each mixed expense.

b$.$ Compute the company's total contribution margin for May.

With explanation please.