Seinfield Corporation purchased an equipment cost $150,000 at Jan 1, 2014 and the company estimated that the equipment would have a salvage value of $30,000 at the end of its service life. 1- Assume that the company sold the equipment at the end of its useful life for $40,000 cash. What is the gain or loss on disposal? 2- If the book value of the equipment at the first year was $130,000 using straight-line method, what is the estimated useful life? (use depreciation schedule) 3- If the book value of the equipment at the first year was $114,000 using unit of production method, what is the estimated working hours (assume that the working hours of the first year was 3,000 hours)? (use depreciation schedule) 4- If the company sold the equipment at June 30, 2016 for $45,000, what is the gain or loss on disposal? (using straight line method)