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A scientist wants to find the average mass of fish living in a large pond. So she will use the masses of a sample of fish from the pond to find the average mass.
Answer the questions below.

(a) Which unit(s) could be used for the unit of measurement? Check all that apply.

1.) minutes

2.) kilograms

3.) grams

4.) milligrams

5.) seconds

(b) Which of the procedures below would be the best way to find the average mass?

1.) Pick 2 fish from a shallow region of the pond and weigh each of them.

2.) Pick 42 fish from a shallow region of the pond and estimate their masses.

3.) Randomly pick 2 fish from the entire pond and estimate their masses.

4.) Randomly pick 42 fish from the entire pond and weigh each of them.