You are given the following linear programming model and Excel spreadsheet to solve this problem : MAX:$25$x$1+35$x$2$ Subject to:$6$x$1+4$x$2<=15000$What formula should be entered in cell D$8$ in the accompanying Excel spreadsheet to compute the LHS of constraint $1?$ Choose a formula that can subsequently be copied from the cell D$8$ and pasted to cells D$9$ and D$10?$

Group of answer choices

$=$ SUMPRODUCT$($B$8$:C$8,$ B$4$:C$4)$

$=$ SUMPRODUCT$($B$8$:C$8,$$B$$4$:$C$$4)$

$=$SUM$($B$5$:C$5)$

$=$SUM$($E$8$:E$10)$

Group of answer choices

$=$B$4*$B$5+$C$4*$C$5$

$=$SUMPRODUCT$($B$8$:C$8,$$B$$4$:$C$$4)$

$=$SUM$($B$5$:C$5)$

$=$SUM$($E$8$:E$10)$