Is Dana school closes a phone tree is used contact each students family the secretary calls three families then each family calls 3 other families and so on, how many families will be notified by the sixth round of calls?

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

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?

Can someone me with my math problem pls my teacher is on my back about this