Answer:

Explanation:
Given
The data in the table
Required
Follow the steps appended to the question;
Step 1: Calculate the Mean or Average
Mean = Summation of lengths divided by number of teams;



Step 2: Get The Range



Step 3: Divide Range by 2



Step 4: Determine the Precision

Substitute 2.70 for Average and 0.1 for Approximate Range

Ions are formed when atoms lose or gain electrons in order to fulfill the octet rule and have fuller valence electron shells.
15 ppm
1.5 × 10-2 ppm
1.5 × 104 ppm
3.1 ppm
1.5 × 10-2 ppm