Does the following statement use significant figures correctly?

A total of 9,832,456 copies of the 67^th issue of a journal were sold in 2023.

Determine whether the number is exact or not exact. Note that the number of significant figures of exact numbers is unlimited.

1 ton = 2000 lbs

Select the exact numbers from the following:

(a) the mass of a black ballpen

(b) the average height of buildings around the park

(c) the number of liters in a cubic feet of water

(d) the number of employee in an office

(e) the mass of a soda can

True or False: A decrease in the number of significant figures results in an increase in the level of certainty in the measurement.

The three dartboards shown below are produced by: Person A an expert using their own darts; Person B only played darts a few times; and Person C a new player of darts. For Person B and Person C to have the same results as those in Person A, which of the following should happen?

The true percentage of lead in a sample is 30.56%. Two students measured the percentage for three determinations. Calculate the average percentage for each set of data.

Student 1: 30.55, 30.54, 30.53

Student 2: 30.53, 30.57, 30.56

State which student had a more accurate measurement based on the average.