On a mission to a newly discovered planet, an astronaut finds gallium abundances of 61 29 % for ^69 Ga and 39 71 % for ^71Ga. What s the atomic mass of gallium for this location? The mass of ^69 Ga is 68 7200 amu. The mass of ^71 Ga is 70 9200 amu. Express your answer to two decimal places, and include the appropriate units. The astronaut then measures the abundance of magnesium on the new planet, obtaining the following results.