a$)$ A manager is using a linear regression model, as depicted below, to forecast quarterly demand for a product:

Yt $=6,000+80$t where t $=0$ at Q$2$ of last year

Quarterly relatives are Q$1=0\mathrm{.}6,$ Q$2=0\mathrm{.}9,$ Q$3=1\mathrm{.}3,$ and Q$4=1\mathrm{.}2.$

What forecasts are appropriate for the last quarter of this year and the first quarter of next year?