Looking at the deferred tax assets and liabilities of Apple's 10-K for Fiscal Year ended September 28, 2019, please answer the following:

1. What are Apple's 2019 gross deferred tax liabilities?

2. What is the largest category of deferred tax liabilities for Apple at the end of 2019?

3. What is the largest category of deferred tax assets for Apple at the end of 2019?

4. Historically, has Apple deducted more depreciation and amortization expense for tax purposes or financial statement purposes? How can you tell?

5. Estimate the aggregate tax basis in 2019 of Apple's Property, Plant and Equipment. For simplicity, assume the deferred tax asset for depreciation and amortization relates solely to property, plant, and equipment. For simplicity, assume any deferred taxes related on those items were recorded at a 21% tax rate. Is the estimate likely overstated or understated?

6. How do you think the deferred tax asset for "accrued liabilities and other reserves" arises? Specifically, does it indicate that the company is recognizing estimated expenses sooner for accounting than for tax purposes or does it indicate that the company is recognizing estimate expenses sooner for tax than for accounting purposes?