1a. Air in a hot air balloon does 37 J of work while expanding, and also absorbs 74.8 of heat from a heat source. What is the change in the balloon air's internal energy?

1b. An aluminum wing on a passenger jet is 26 m long when the temperature is 28.5 degrees Celsius. Using eBook Table 5.2, at what temperature (in degrees Celsius) would the wing be 1 mm shorter?

1c. How much heat (in Joules) is needed to raise the temperature of 1.1 kg of aluminum from 20 degrees Celsius to 919 degrees Celsius?