$10.$ Given the following financial information:

$--$ MR $=$ MC $=$ $$5\mathrm{.}00$ at output level $($Q$)=30$;

$--$ ATC $=$ $$5\mathrm{.}50$;

$--$ AVC $=$ $$4\mathrm{.}50$

Using the data as presented above of a perfectly competitive firm,

a$.$ the competitive firm should shut down immediately

b$.$ the competitive firm is operating at a loss at $$15$ but should keep the operation going

c$.$ the competitive firm's TFC is $$30$ had the firm decided to shut down

d$.$ existing firms would leave the industry until MR is tangent to

ATC at $$5\mathrm{.}50$ in the long run

e$.$ firms would enter the industry until MR is tangent to ATC at $$5\mathrm{.}50$ in the long run

$$ only b$,$ c$,$ d are correct

$$ only e is correct

$$ only b and c are correct

$$ every one of the answers is correct