Determining Missing Items in Return Computation

One item is omitted from each of the following computations of the return on investment:

Determine the missing items identified by the letters as shown above. If required, round your answers to two decimal places.

$($a$)$

$($b$)$

$\%$

$($c$)$

$\%$

$($d$)$

$($e$)$

$\%$