Question $3.(25/100)$

The above table is about statistics in a coal company, including time period $($Year and

Quarter$),$ number of employees and coal sales.

Task $1$: Since number of employees seems to be stable, it is better to leverage Heuristics

methods to analyze it$.$ In this task, you need to use Simple Exponential Smoothing

method $($with $=0\mathrm{.}7)$ to predict the number of employees in $2022$Q$2,2022$Q$3,$

$2022$Q$4,2023$Q$1,2023$Q$2,2023$Q$3,$ and $2023$Q$4$ respectively. Moreover, please

calculate the MAD, Standard Error, and MAPE for your prediction. $($Keep values in $3$

decimal places.$)$