Answer:

Step-by-step explanation:
Let's start by using change of base property:

So, for 

Now, using change of base for 

You can express
as:

Using reduction of power property:


Therefore:

As you can see the only difference between (1) and (2) is the coefficient
:
So:


Answer: She would have to burn between 220 and 240 calories per minute to have a calorie burn rate between those of Martin and Paul.
Step-by-step explanation:
Martin:
360 calories / 30 min = 12 calories/min
Paul:
165 calories / 15 min = 11 calories/min
Kara:
Needs to burn between 11 and 12 calories/min, so we'll calculate the range:
11 calories/min x 20 min = 220 calories (minimum # calories she can burn)
12 calories/min x 20 min = 240 calories (maximum # calories she can burn)