Tim is building a model of a castle with small wooden cubes. So far, Tim has constructed part of a security wall of the castle, as shown below. Each wooden cube has a side length of ft. Based on the model, the length of the wall is ft, the width of the wall is ft, and the height of the wall is ft. The volume of the portion of security wall that Tim has constructed so far is cu ft.

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?