Arsenic is toxic to humans. the greatest amount of arsenic that is allowed in drinking water is 10 parts per billion. a test shows that a source of drinking water contains 0.000002% arsenic. is this an allowable amount? explain.

The decimal you put would be “two ten-millionths” if read out loud. If the allowable amount is 10 parts per billion, it would be 1 part per 100 million. Because 2 parts per 10 million is also 20 parts per 100 million, it is not not an acceptable amount