Workers are compensated by firms with "benefits" in addition to wages and salaries. the most prominent benefit offered by many firms is health insurance. suppose that in 2000, workers at one steel plant were paid $20 per hour and in addition received health benefits at the rate of $4 per hour. also suppose that by 2010 workers at that plant were paid $21 per hour but received $9 in health insurance benefits. by what percentage did the wage change at this plant from 2000 to 2010?

Wo firms, a and b, each currently dump 50 tons of chemicals into the local river. the government has decided to reduce the pollution and from now on will require a pollution permit for each ton of pollution dumped into the river. it costs firm a $100 for each ton of pollution that it eliminates before it reaches the river, and it costs firm b $50 for each ton of pollution that it eliminates before it reaches the river. the government gives each firm 20 pollution permits. government officials are not sure whether to allow the firms to buy or sell the pollution permits to each other. what is the total cost of reducing pollution if firms are not allowed to buy and sell pollution permits from each other? what is the total cost of reducing pollution if the firms are allowed to buy and sell permits from each other? a. $3,000; $1,500 b. $4,500; $3,500 c. $4,500; $4,000 d. $4,500; $2,500