Using the following time series $($monthly sales level for a specific model of car$)$ to answer the next $4$ questions:

Year Quarter Sales Level

$2022$ Quarter $13500$

Quarter $213100$

Quarter $315800$

Quarter $47600$

$2023$ Quarter $111200$

$17.$ Use the stationary method to forecast sales for the second quarter of $2023.$

a$.11045\mathrm{.}6$

b$.987\mathrm{.}8$

c$.10240\mathrm{.}0$

d$.11200\mathrm{.}0$

e$.7600$