repare a forecast for period n through $6$ using each of these approaches:

$1.$ The appropriate naive approach.

$2.$ A three$-$period moving average.

$3.$ A three$-$period weighted average using weights of $0\mathrm{.}50,0\mathrm{.}30,$ and $0\mathrm{.}20.$

$4.$ Exponential smoothing with a smoothing constant of $0\mathrm{.}40.$ Use $60$ as

forecast for week $2.$