The temperature in Gavin's oven is a sinusoidal function of time. Gavin sets his oven so that it has a maximum temperature of280Fand a minimum temperature of240. Once the temperature hits280, it takes20 minutesbefore it is280again. Gavin's cake needs to be in the oven for30 minutesat temperatures at or above270. He puts the cake into the oven when it is at260and rising. How long will Gavin need to leave the cake in the oven? (Round your answer to the nearest minute.)

______________min.