Answer
$1116\;ft^3/min.$
Work Step by Step
The given supply air requirements:-
$A=120\;ft^3/min.$
$B=265\;ft^3/min.$
$C=61\;ft^3/min.$
$D=670\;ft^3/min.$
Add all the given air supply.
$=A+B+C+D$
Substitute all values.
$=120\;ft^3/min.+265\;ft^3/min.+61\;ft^3/min.+670\;ft^3/min.$
$=1116\;ft^3/min.$
Hence, the required HVAC unit supply air flow is $1116\;ft^3/min.$
