Please help i'll mark big brain

Which of the following situations represents a linear relationship? a. theresa increases the distance she runs by 0.1 miles every week. b. the volume of a box depends on the length of box. c. the amount of money in a bank account increases by 1 percent each year. d. the population of a town doubles every 5 years.

What situation is an example of an observational study

Thelime contains the point(-3,0) and parallel x-3y=3( show all work)