Acertain forest covers an area of 4700 km^2. suppose that each year this area decreases by 3%. what will the area be after 9 years?

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Data from 2005 for various age groups show that for each $100 increase in the median weekly income for whites, the median weekly income of blacks increases by $105. also, for workers of ages 25 to 54 the median weekly income for whites was $676 and for blacks was $527. (a) let w represent the median weekly income for whites and b the median weekly income for blacks, and write the equation of the line that gives b as a linear function of w. b = (b) when the median weekly income for whites is $760, what does the equation in (a) predict for the median weekly income for blacks?

The angle of elevation from point a to the top of a cliff is 38 degrees . if point a is 80 feet from the base of the cliff , how high is the cliff ?