Gallium has a weighted average atomic mass of 69.7 and two naturally occurring isotopes: gallium-69 and gallium-71. Gallium-69 has a relative abundance of 60.1% and a mass of 68.9. The relative abundance of gallium-71 is 39.9%. Based on this information, what is the mass of gallium-71?

71.1 g/mol
71.0 g/mol
70.9 g/mol
70.8 g/mol