The high low level of activity last year was 60,000 units of product produced in May and 20,000 units produced in November. Machine maintenance costs were $39,000 in May and $15000 in November. using High-Low method , determine an estimate of total maintenance cost for a month in which production is expected to be 45,000 units
a) 36,000
b )29,500
c) 33,700
d) 30,000