Question

question 7 1 pts units such as parts per million (ppm) or parts per billion (ppb) are used to express __________ concentrations of solutes. undetectable moderately high very low very high question 8 1 pts percentage, like units such as parts per million (ppm) or parts per billion (ppb) can be thought of as \____________\. part per one hundred thousand part per thousand fractions part per hundred

Explanation:

For Question 7, ppm and ppb are used for very low - concentration solutes as they represent small amounts relative to the total solution. For Question 8, percentage is a part per hundred, and like ppm and ppb, it is a way of expressing a ratio or fraction of a component in a mixture.

Answer:

Question 7: C. very low
Question 8: D. part per hundred