Zeigler Manufacturing Company purchased a robot for $720,000 at the beginning of year 1. The robot has an estimated useful life of 4 years and an estimated residual value of $60,000. The robot, which should last 20,000 hours, was operated:

6,000 hours in year 1;

8,000 hours in year 2;

4,000 hours in year 3; and

2,000 hours in year 4.

Required

1. Compute the annual depreciation and carrying value for the robot for each year

assuming the following depreciation methods:

(a) straight-line,

(b) production, and

(c) double-declining-balance.

2. If the robot is sold for $750,000 after year 2, what would be the amount of gain or

loss under each method?