Asronomy/physics problem, need some guidance!

The Moon’s density is 3.3 kg/L. Suppose that the Moon is made of just two substances: silicates with a density of 3.0 kg/L and iron with a density of 7.9 kg/L. a. What fraction of its mass must be iron? b. What fraction of its volume must be iron?
Asked Dec 05, 2013

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