The classification of service with the highest level of customization and labor (and thus the highest cost) is:

Professional service

Explanation:

Professional service is the classification of service with the highest level of customization and labor (and thus the highest cost).

Professional services are basically the ccupations that we have in the service sector whereby some sort of special training are required in that particular field. It should be noted that for some professional services, one must possess professional degrees. Examples of professional services are accounting, banking etc.

$0.29 per mile

Explanation:

Truck is to be driven for 100,000 miles.

It has a cost of $34,000 and a salvage value of $5,000.

Useful life is 8 years.

Depreciable cost per mile under units-of-activity method = (Cost price - Salvage value) / Miles to be driven

= (34,000 - 5,000) / 100,000

= $0.29 per mile