Before coin and paper money, how did people people exchange goods and services

Suppose that a paving company produces paved parking spaces (q) using a fixed quantity of land (t) and variable quantities of cement (c) and labor (l). the firm is currently paving 1,000 parking spaces. the firm's cost of cement is $3 comma 600.003,600.00 per acre covered (c) and its cost of labor is $35.0035.00/hour (w). for the quantities of c and l that the firm has chosen, mp subscript upper c baseline equals 60mpc=60 and mp subscript upper l baseline equals 7mpl=7. is this firm minimizing its cost of producing parking spaces?

Schuepfer inc. bases its selling and administrative expense budget on budgeted unit sales. the sales budget shows 1,800 units are planned to be sold in march. the variable selling and administrative expense is $4.30 per unit. the budgeted fixed selling and administrative expense is $35,620 per month, which includes depreciation of $2,700 per month. the remainder of the fixed selling and administrative expense represents current cash flows. the cash disbursements for selling and administrative expenses on the march selling and administrative expense budget should be:

Greentel, a telecom giant, has been using the service of orpheus inc. for training its employees. according to a deal signed by the two companies, orpheus inc. is not only responsible for training greentel's employees but also for providing comprehensive administrative services to the telecom giant. in this instance, greentel engages in