Correct: About 70% of earth is covered by water, Only 3% of earth’s water is usable., Most water is unusable because it has salt., Water can also be unusable because it is frozen or underground; or it is contaminated, Water sources of fresh water: lake, river…, Incorrect: About 60% of earth is covered by water, Only 10% of earth’s water is usable., Most water is usable because it has salt., Water can also be usable because it is frozen or underground; or it is contaminated, Water sources of fresh water: ocean,

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