Answer:
After 5 hours, the amount of bacteria increased: 7800-6000=1800
After 1 hours, the amount of bacteria increased: 1800/5=360
After 18 hours, the amount of bacteria increased: 360*18 = 6480
=> Total amount of bacteria after 13 hours: 6000+6480 =12480
Im not sure but since the angle you have is 52 and this is an isosceles triangle so you will do 180-52 over 2 to get the other 2 angles which will be 64 each and you want the exterior angle which is 180 aswell so you will do 180-64 which will be 116
is there not a graph to this????