The price per gallon of gasoline changes often. Most drivers pay close attention to those changes. Find the percent change in price for each of these cases.
Aincrease from $4.00 per gallon to $4.20
Bincrease from $3.00 per gallon to $3.75
Cdecrease from $3.75 per gallon to $3.00
Aincrease from $4.00 per gallon to $4.20
Bincrease from $3.00 per gallon to $3.75
Cdecrease from $3.75 per gallon to $3.00