4B. Beginning with a regular hexagon, a 6-pointed star is formed by constructing equilateral triangles, whose sides are the same length as the sides of the hexagon, on each side of the hexagon as shown. One of the equilateral triangles is shaded. The shaded area is what fractional part of the entire area of the 6-pointed star? Express the answer as a fraction in simplest form.

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?