HEL PLEASSEEE How many moles are present in 4.20 x 10^26 molecules of water?
A. 700 moles
B. 0.7 moles
C. 70 moles
D. 25.2 moles

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3