explain the following question?

51) What is the purpose of adjusting entries? Discuss the effect of not preparing adjusting entries on various accounts. 52) What are the differences between depreciation expense and accumulated depreciation? 53) Equipment was purchased for $20,000, residual value is $1,000 and it is expected that the useful life is 10 years. What is the depreciation adjustment after the first year assuming straight-line depreciation? 54) Equipment was purchased for $20,000, residual value is $1,000 and it is expected that the useful life is 10 years. What is the book value of the equipment after the first year assuming straight-line depreciation