Which of the following is a reason why full-cost pricing is not more widely used? a. Environmental and health costs are difficult to estimate. b. Most producers of harmful products and services would not have to charge more for them. c. Environmentally harmful companies hesitate to obtain tax breaks and government subsidies to increase profits and stay in business. d. Environmentally harmful companies are reluctant to use political and economic power. e. Such an approach is not realistic for solving environmental problems