you are a particular bright cavemen tired of living in an unheated and unlighted cave. in front of you are two geysers (continuously flowing fountains of hot water). geyser a puts out 1 kg/s of water at a temperature of 310k while geyser b puts out 0.15 kg/s of water at a temperature of 370 k. the ambient temperature is 290 k. you wish to use one geyser to heat your cave and another to run a rock breaking engine. which geyser should be used for each operation?