Please explain the solution to this general accounting problem using the correct accounting principles.

subject = general accounting question

Accounting?

Faith Industries purchased a crane for $78,000 on January 1, 2021. The crane has an expected salvage value of $6,000 and is expected to be used for 120,000 hours over its estimated useful life of 8 years. Actual usage was 13,800 hours in 2021 and 15,400 hours in 2022. Calculate depreciation expense per hour under the units-of-activity method. (Round the answer to 2 decimal places.)

Accurate Answer

Kellogg Corporation uses a single raw material in its production process. The standard price for a unit of material is $3.25. During the month, the company purchased and used 680 units of this material at a price of $3.40 per unit. The standard quantity required per finished product is 2 units, and during the month, the company produced 325 finished units. How much was the material quantity variance?

I am searching for the accurate solution to this financial accounting problem with the right approach.

general accounting question

Hendrix Plumbing Services purchased machinery for $18,400 on March 1, 2022. The machinery has an estimated useful life of 8 years and a residual value of $1,600. Hendrix uses the straight-line method to calculate depreciation and records depreciation expense at the end of every month. As of September 30, 2022, the book value of this machinery shown on its balance sheet will be: A. $17,175 B. $16,800 C. $16,550 D. $18,400