Problem $18-3($Algo$)$

Given the following history, use a three$-$quarter moving average to forecast the demand for the third quarter of this year. Note: the $1$st quarter is January, February, and March; $2$nd quarter April, May, June; $3$rd quarter July, August, September, and $4$th quarter October, November, December.

$\backslash$table$[[,$JANUARY,FEBRUARY,MARCH,APRIL,MAY,JUNE,JULY,AUGUST,SEPTEMBER,OCTOBER,NOVEMBER,DECEM$],[$Last year,$120,140,145,195,205,220,165,155,145,220,245,26$:$],[$This year,$140,145,200,210,240,255,,,,,,]]$