Suppose the Accompanying Table Describes the Demand for a Good

Multiple Choice

Suppose the accompanying table describes the demand for a good produced by monopolist.  
$$\begin{array} { | c | c | } \hline \text { Price } & \text { Quantity } \\\hline \$ 10 & 1 \\\hline \$ 9 & 2 \\\hline \$ 8 & 3 \\\hline \$ 7 & 4 \\\hline \$ 6 & 5 \\\hline \$ 5 & 6 \\\hline \$ 4 & 7 \\\hline\end{array}$$
The total revenue from selling 6 units is ________, and the marginal revenue of selling the 6?? unit is ________. 

A) $5; 5
B) $30; 0
C) $24; $5
D) $30; $1