Marine Expeditors has three divisions. Division A is the core of the business and represents $80$ percent of the firm's operations. Division B is involved only with contractual short$-$term projects and therefore has about ten percent less risk than Division A$.$ Division C develops and markets new products and is about ten percent riskier than Division A and about equal in size to Division B$.$ The manager of Division A has suggested that the operations of his division be increased by $10$ percent next year. The proposed project should probably be assigned a required return that is equal to $\_\_\_\_\_\_\_\_$ percent of the firm's weighted average cost of capital. I know it's $100\%$ which comes from $80+10+10$ but there does the $80$ and $10$s come from??