Hydro Systems Engineering Associates, Inc., provides consulting services to city water authorities. The consulting firm's contributionmargin ratio is 25 percent, and its annual fixed expenses are $295,000. The firm's income-tax rate is 40 percent. Required: 1. Calculate the firm's break-even volume of service revenue. 2. How much before-tax income must the firm earn to make an after-tax net income of $158,000 ? 3. What level of revenue for consulting services must the firm generate to earn an after-tax net income of $158,000 ? 4. Suppose the firm's income-tax rate changes to 30 percent. What will happen to the break-even level of consulting service revenue