Emma is keeping track of the temperature in a pond for her science experiment. each day, the temperature changes - 1.2 degrees . what will the change in temperature be after 7 days?

after 7th day the temperature changes - 8.4 degrees.

Step-by-step explanation:

Each day, the temperature changes - 1.2 degrees. Then

after 1st day the temperature changes - 1.2 degrees;after 2nd day the temperature changes - 2.4 degrees;after 3rd day the temperature changes - 3.6 degrees;after 4th day the temperature changes - 4.8 degrees;after 5th day the temperature changes - 6 degrees;after 6th day the temperature changes - 7.2 degrees;after 7th day the temperature changes - 8.4 degrees.

Monthly service fee is like the fixed cost which is basically the y-value where graph crosses the y-axis.

From graph we see that graph crosses at 1 on y-axis so monthly service fee according to sample graph = $1

Now the per check fee works like slope of the line.

To find the slope we need two points so find any two points on the graph of line. I'm using points (1,0) and (4,3)

now slope can be found using formula

Hence per check fee will be $0.5 as per attached sample graph.

You can use same technique for the original graph given with this question.

Step-by-step explanation: