If Perteet corporation produces 7,000 units, the variable manufacturing overhead cost shall be 7,000 units * $1.50 = $10,500
And fixed manufacturing overhead shall remain same in totality, hence fixed manufacturing overhead cost shall be 11,000 units *$3 = $33,000
The total amount of manufacturing overhead cost = 10,500+33,000 = $43,500
Hence, the total amount of manufacturing overhead cost at the level of 7,000 units production shall be $43,500