Calculate the atomic mass of gallium, symbol Ga. Gallium has two isotopes: Ga-69 and Ga-71. The relative abundance of Ga-69 is 60.12% and its atomic mass is 68.9257 amu, The relative abundance of Ga-71 is 39.88% and its atomic mass is 70.9249 amu.
A)
69.7241 amu
B)
69.9262 amu
70 amu
D
70.0000 amu

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Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.