The revenue from a companys
socks is a function of the price they charge. The price
they can charge is a function of demand. Currently the
demand is dropping at a rate of 1000 ringtones per day.
The marginal price (as a function of demand) currently is
$.00001 per extra ringtone demanded .

What is the current marginal price as a function
of time?


if the current price of socks is $1.13 and the
current demand is 5000 socks, then
what is the current marginal revenue as a
function of time?