$6.$ Firm E operates in a jurisdiction that levies an income tax with the following rate structure:

Rate Bracket

$7\%$ Income from $$0$ to $$75,000$

$10\%$ Income from $$75,001$ to $$150,000$

$15\%$ Income in excess of $$150,000$

Firm E has the opportunity to invest in a business project that should generate $$20,000$ of additional taxable income for the year. Compute the tax cost of this additional income assuming that:

a$)$ Firm E$$s taxable income before considering the additional income is $$130,000$