Assume that a demand equation is given by $x=9000-100p.$ Find the marginal revenue for the given production levels $($values of $x).($Hint: Solve the demand equation for $p$ and use $R(x)=xp.)$

$($a$)2500$ units

$($b$)4500$ units

$($c$)7000$ units

What is the marginal revenue function, $R^{\text{'}}(x)?$

$R^{\text{'}}(x)=90-0\mathrm{.}02x$

$($a$)$ Choose and fill in the correct response for $x=2500.$

A$.$ The marginal revenue at $$ units is $$2500$ per production level.

B$.$ The marginal revenue at $$ units is $2500$ production levels per $$1.$

C$.$ The marginal revenue at $2500$ units is $$ production levels per $$1.$

D$.$ The marginal revenue at $2500$ units is $?q,$ per production level.