Suppose that a submarine inadvertently sinks to the bottom of the ocean at a depth of 1000m. it is proposed to lower a diving bell to the submarine and attempt to enter the conning tower. what must the minimum air pressure be in the diving bell at the level of the submarine to prevent water from entering into the bell when the opening valve at the bottom is cracked open slightly? give your answer in absolute kilopascal. assume that seawater has a constant density of 1.024 g/cm3.

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.)