Use the Following General Linear Demand Relation to Answer Questions $$Q _ { d } = 680 - 9 P + 0.006 M - 4 P _ { R }$$

Multiple Choice

Use the following general linear demand relation to answer questions : $$Q _ { d } = 680 - 9 P + 0.006 M - 4 P _ { R }$$ where M is income and $P _ { R }$ is the price of a related good, R.
-If M = $15,000 and $P _ { R }$ = $20 and the supply function is $Q _ { s } = 30 + 3 P$ , then, when the price of the good is $60,

A) there is a shortage of 60 units of the good.
B) there is equilibrium in the market.
C) there is a surplus of 60 units of the good.
D) the quantities demanded and supplied are indeterminate.