$3-$month Period Demand $($units$)$

Jan$-$Mar $2022$

$3200$

Apr$-$Jun $2022$

$3600$

Jul$-$Sep $2022$

$3600$

Oct$-$Dec $2022$

$4000$

Jan$-$Mar $2023$

$2600$

Apr$-$Jun $2023$

$2400$

Jul$-$Sep $2023$

$2400$

Oct$-$Dec $2023$

$2200$

Using Winter$$s method, calculate the one$-$step and two$-$step demand forecasts for the upcoming two

$3-$month periods $($i$.$e$.,$ Jan$-$Mar $2024$ and Apr$-$Jun $2024).$ Show each step of your work.

Suppose that the demand for Apr$-$Jun $2024$ turns out to be $2200$ units. What is the MAPE value for

your two$-$period$-$ahead forecasts? That means you can only use your Apr$-$Jun $2024$ forecast from part

a$.$