I need help with 3,4 6,7 8 9 and 10 please

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?

Which statements about the system are true? check all that apply. y =1/3 x – 4 3y – x = –7 the system has one solution. the system consists of parallel lines. both lines have the same slope. both lines have the same y–intercept. the equations represent the same line. the lines intersect.

Using only the digits 5, 6, 7, 8, how many different three digit numbers can be formed if no digit is repeated in a number?