$3\mathrm{.}57$ Consider the cash flow shown in the accompanying diagram. What value of $\backslash ($ C $\backslash )$ makes the inflow series equivalent to the outflow series at an interest rate of $\backslash (10\backslash \%\backslash )?$

$\backslash (\backslash$$ $500\backslash )$

Figure P$3\mathrm{.}57$

$3\mathrm{.}66$ At what rate of interest compounded annually will an investment double in five years?

$3\mathrm{.}68$ You have $\backslash (\backslash$$ $15,000\backslash )$ available for investment in stock. You are looking for a growth stock whose value can grow to $\backslash (\backslash$$ $40,000\backslash )$ over five years. What growth rate are you looking for?

$3\mathrm{.}69$ How long will it take to save $\backslash (\backslash$$ $1\backslash )$ million if you invest $\backslash (\backslash$$ $2,000\backslash )$ each year at $\backslash (6\backslash \%\backslash )?$

I have tried this one, but I am not sure if the image and the calculations even line up$,$ since my values do not appear to make any sense in regards to the chart. I would appreciate an expanded explanation of the process leading up to the solution, thank you.