accounting for overheads

The fixed overhead absorption rate is $8 per direct labour hour.

The labour budget for this year is

– skilled production $360,000
– unskilled production $180,000
– factory supervision $120,000

Skilled production workers are paid $4 per hour, unskilled workers are paid $3 per hour and supervisors are paid $6 per hour.
What is the budgeted fixed overhead for the year?

here why factory supervision is not taken in to calculation why and explain
ans:
Number of labour hours = ?360 ,000 /4 + 1 80 ,000 / 3? = 150,000

Therefore this year’s overheads = 150,000 × $8 = $1,200,000