help???? I don't understand conversion factors
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1. There are 41.99 grams in 4.5 moles of sodium fluoride.
2. There are 1.26 moles in 98.3 grams of aluminum hydroxide.
3. There are 5 grams in 0.02 moles of beryllium iodide.
4. There are 0.70 moles in 68 grams of copper (II) hydroxide.
5. There are 0.064 grams in 2.3x10^-4 moles of calcium phosphate.