Amazon.com Inc. is planning its tax strategy for the upcoming fiscal year. The company's taxable income is projected to be $10 billion. Considering Amazon's tax rate of 21%, calculate: a) The amount of taxes Amazon is expected to pay. b) If Amazon decides to invest $2 billion in research and development (R&D), which qualifies for a tax credit of 10%, how much will the company save in taxes? c) Assuming Amazon takes advantage of accelerated depreciation on its new fulfillment centers, which allows for a depreciation expense of $500 million, calculate the tax shield provided by depreciation.