The molecular mass of helium is 4 g/mol, the Boltzmann's constant is 1.38066 × 10-23 J/K, the universal gas constant is 8.31451 J/K · mol, and Avogadro's number is 6.02214 × 1023 1/mol. Given: 1 atm = 101300 Pa. How many atoms of helium gas are required to fill a balloon to diameter 32 cm at 77?C and 1.271 atm? What is the average kinetic energy of each helium atom? What is the rms speed of each helium atom?