The number $Q$ of people taking city buses at price $p$ dollars per ticket is $$Q = 5000\sqrt{6-p}\ .$$

(a) Evaluate the demand elasticity $E$ when $p = 2$.
$E(2)=$

Here, "demand elasticity" is the absolute value of $\displaystyle \frac{\text{percent change in quantity}}{\text{percent change in price}}$ for an infinitesimal change in price, so $$E = \left| \lim_{\Delta p \to 0} \frac{ \Delta Q / Q}{\Delta p / p} \right| \ .$$

(b) Currently, the price per ticket is 2 dollars. Should the price be raised in order to increase revenue? ?? Yes No

(c) For what value of $p$ is the demand elasticity unitary?
$p=$

(d) What is the maximum revenue?
Maximum Revenue =