dogs are able to hear much higher frequencies than humans are capable of detecting. for this reason, dog whistles that are inaudible to the human ear can be heard easily by a dog. if a dog whistle has a frequency of 3 hz, what is the wavelength of the sound emitted?

The temperature in gavin's oven is a sinusoidal function of time. gavin sets his oven so that it has a maximum temperature of 280°f and a minimum temperature of 240°. once the temperature hits 280°, it takes 20 minutes before it is 280° again. gavin's cake needs to be in the oven for 30 minutes at temperatures at or above 270°. he puts the cake into the oven when it is at 260° and rising. how long will gavin need to leave the cake in the oven? (round your answer to the nearest minute.)