The temperature in Gavin’s oven is a sinusoidal function of time. Gavin sets his oven so that it has a maximum tem- perature of 300◦F and a minimum tempera- ture of 240◦ . Once the temperature hits 300◦ , it takes 20 minutes before it is 300◦ again. Gavin’s cake needs to be in the oven for 30 minutes at temperatures at or above 280 ◦. He puts the cake into the oven when it is at 270 and rising. How long will Gavin need to leave the cake in the oven?