Answer:
The formula in Excel is:
=($B$6 - $B$5 - $B$7)* $B$8
Explanation:
Required
Use of absolute reference
To reference a cell using absolute reference, we have to include that $ sign. i.e. cell B5 will be written as: $B$5; B6 as $B$6; B7 as $B$7; and B8 as $B$8;
Having explained that, the formula in cell B13 is:
=($B$6 - $B$5 - $B$7)* $B$8