Using the information below, what is the price$-$earnings ratio for DEF Company? $($Hint: this is a two step calculation$)$

After$-$tax income $=$$$150,000$

Number of shares outstanding $=60,000$

Price per share $=$$$30$

Book value per share $=$$$10$

Select one:

a$.$ $$4\mathrm{.}00$

b$.$ $$7\mathrm{.}50$

c$.$ $$12\mathrm{.}00$

d$.$ $$20\mathrm{.}00$