$\backslash$table$[[$Output$,\backslash$table$[[$Average$],[$Fixed$],[$Cost$]],$Average Variable Cost$],[1,$$$50\mathrm{.}00,$$$100\mathrm{.}00],[2,25\mathrm{.}00,80\mathrm{.}00],[3,16\mathrm{.}67,66\mathrm{.}67],[4,12\mathrm{.}50,65\mathrm{.}00],[5,10\mathrm{.}00,68\mathrm{.}00],[6,8\mathrm{.}37,73\mathrm{.}33],[7,7\mathrm{.}14,80\mathrm{.}00],[8,6\mathrm{.}25,87\mathrm{.}50]]$

$|13.$ Refer to the above data. The total cost of four units of output is:

A$.$ $$260.$

B$.$ $$77\mathrm{.}50.$

C$.$ $$310.$

D$.$ $$215.$

$14.$ Refer to the above data. If the firm shut down and produced zero units of output, its total cost would be:

A$.$ zero.

B$.$ $$50.$

C$.$ $$150.$

D$.$ $$100.$

$15.$ Refer to the above data. The marginal cost of the fifth unit of output is:

A$.$ $$3.$

B$.$ $$62.$

C$.$ $$80.$

D$.$ $$78.$

$16.$ Refer to the above data. The marginal cost curve would intersect the average variable cost curve at about:

A$.2$ units of output.

B$.4$ units of output.

C$.6$ units of output.

D$.7$ units of output.

$17.$ Refer to the above data. If the firm decided to increase its output from $6$ to $7$ units, its total costs would rise by:

A$.$ $$87\mathrm{.}14.$

B$.$ $$80\mathrm{.}00.$

C$.$ $$6\mathrm{.}67.$

D$.$ $$120\mathrm{.}00.$