A golf ball manufacturer knows the cost associated with various hourly production levels, given below.

Production Costs for Golf Balls

numerical values to three decimal places.$)$

$c(b)=$

dollars

$($b$)$ If $1000$ balls are currently being produced each hour, calculate the marginal cost at that level of production. $($Round your answer to three decimal places.$)$

$

$\backslash$times per hundred balls

Interpret the result. $($Round your numerical answer to three decimal places.$)$

At an hourly production level of $1000$ golf balls, production cost is

by $

per hundred golf balls.

numerical values to three decimal places.$)$

$\frac{?}{\text{b}\text{a}\text{r}}(C)(b)=$

dollars per hundred balls

$($d$)$ Calculate the rate of change of average cost for hourly production levels of $1000$ golf balls. $($Round your answer to three decimal places.$)$

$

$|$ per hundred balls per hundred balls

Interpret the result. $($Round your numerical answer to three decimal places.$)$

At an hourly production level of $1000$ golf balls, average production cost is $---$ Select$---$ by $

per hundred golf balls per hundred golf balls.