Question $3$

A new housing development is located at $3$ miles from a smokestack and

exposed to

$1\mathrm{.}4{10}^{-4}m\frac{g}{m^3}$ of benzene.

What is the carcinogenic risk for a $50$ kg adult who breathes the air at $0\mathrm{.}25$

$\frac{m^3}{h}r$ for $8$ hours a day over a period of $5$ years?

$1\mathrm{.}1610-8$

$2\mathrm{.}3210-8$

$410-7$

$810-7$