For the following demand function, find $a.E,$ and $b.$ the values of $q($if any$)$ at which total revenue is maximized.

$p=700e^{-0\mathrm{.}3q}$

a$.$ Find the elasticity of demand $($E$)$ in terms of $q.$

$E(q)=$

b$.$ Find the values of $q($if any$)$ at which total revenue is maximized. Select the correct choice below, and if necessary, fill in the answer box within your choice.

A$.$ Revenue is maximized at $q=$

$($Type an integer or a simplified fraction.$)$

B$.$ No values of q maximize revenue.