5. hailey would like to make a 5 lb coffee mixture that is 60% sumatra coffee bean blend. she has several pounds of a mixture that is 20% sumatra beans and another mixture blend with 80% sumatra beans . let x represent the amount of the 20% blend and y represent the amount of the 80% blend to find out how many pounds of each mixture hailey will need. (a) what is the system that models this situation? (b) what is the solution to the system: show your work.

Ascientist places 24 cells in a petri dish. she knows the cells grow at an exponential rate, doubling in number every hour. how long will it take (in hours) for there to be 1100 cells in the dish? time to 1100 cells: 5.51832530 hours how long will it take to reach 110 cells? time to 110 cells : 2.1963972 hours what is the average rate of change in the number of cells between 9 hours and 11 hours? average rate of change: cells per hour what is the instantaneous rate of change after 7 hours? instantaneous rate of change: cells per hour note: you can earn partial credit on this problem.