Can show me a pic of the problem
Answer:

Step-by-step explanation:
The initial number of cells = 100 and it doubles every hour.
Let the exponential function be

In 1 hour, A = 2P

Therefore, the model of the given situation is given by

3'9" is your answer.
Hope this helps! :)
Answer:
-5
Step-by-step explanation:
The line hits the point (1,2) and (2,-4) and and the rate in change is -5, the line goes 5 down and 1 over which simplifies to -5.
Answer:
Welder A has a better deal because for each hour welder A would charger $75 while welder B would charge $80
Welder A:
300/4 = $75
Welder B:
240/3 = $80