In problem $1,$ suppose that the forecast for January was $75.$ Using single exponential smoothing with $=0\mathrm{.}2,$ compute the exponential smoothing forecast for February through June. What is the Forecast demand for June?

a$.73\mathrm{.}00$ to $74\mathrm{.}00$

b$.75\mathrm{.}00$ to $76\mathrm{.}00$

c$.77\mathrm{.}00$ to $78\mathrm{.}00$

d$.79\mathrm{.}00$ to $80\mathrm{.}00$

$($Please make sure that you know how to work by hand$)$