If it takes you 72 seconds to walk upstairs from the first floor to the fourth floor, how long does it take you to walk from the first floor to the eighth floor? (assume it takes the same amount of time to walk from one floor to next).

Nick has box brads. he uses 4 brads for the first project. nick let’s b represent the original number of brads and finds that for the second project, the number of brads he uses is 8 more than half the difference of b and 4. write an expression to represent the number of brads he uses for the second project.