in the formula for return on investment interest expense is multiplied by (1 - tax rate). Why is this adjustment made? a. Dividends are not deductible for tax purposes are represent returns to common shareholders. b. Interest is not tax deductible c. Debt is excluded from the denominator d. Net income must be adjusted to add back income taxes, net of the related tax benefit, to compute the return to all long-term providers of capital e. US tax reform reduced tax rates in 2018