In October 2005, a family's gasoline consumption is 45 gallons per month and is increasing at a rate of 0. 5 gallons per month. The price of gasoline is 290 cents per gallon and is increasing at a rate of 10 cents per month. Calculate the rate at which the family's monthly gasoline bill is increasing at this time. Give your answer correct to the nearest cent per month. Rate of increase = ? cents per month.