Demand According to economic theory, the demand x for a quantity in a free market decreases as the price p increases (see the figure). Suppose that the number x of DVD players people are willing to buy per week from 1,000 a retail chain at a price of $p is given by x=0.3p+1' 10≤p≤70. Answer parts (A), (B), and (C). 500- Q 250- x= 1,000 0.3p+1 0 40 Price (dollars) 80 Ly

Agriculture At a certain vineyard it is found that each grape vine produces about 10 lb of grapes in a season when about 700 vines are planted per acre. For each additional vine that is planted, the production of each vine decreases by about 1 percent. So, the number of pounds of grapes produced per acre is modeled by An=700+n10-0.01n where n is the number of additional vines planted. Find the number of vines that should be planted to maximize grape production.

Heart Disease In a certain country, the number of deaths due to heart disease decreased from 235 in one year to 221 in the next year. What percentage decrease in deaths due to heart disease does this represent?

Graph on the number line: (a) x2 (b) x3 (c) x1