The slope is 4 or you can think of it as 4/1 if that helps. Remember slope intercept form is y=mx+b.
Answer: The refrigerator cost in this month is $4.5 approximately.
Step-by-step explanation:
Since we have given that
Amount of watt of electric power = 320 W
Number of days = 30
Unit cost of electricity = $0.13/Kwh
Hold factor = 
Number of hours in a month = 24
So, the refrigerator cost in this month would be

Hence, the refrigerator cost in this month is $4.5 approximately.
Let's see all the steps:
1) operation : 5 options
2) only one option: we ignore it
3) the third operation: 6 options
4): 2 options.
So we have 5 options, 6 options and 2 options: and they are independent of each other. This means that we multiply the numbers, and 5*6*2=60 So the answer is 60!
Answer:
all of them that have more than 4 sides