Answer:
B. 95% confident the average concentration of PCBs in the water supply is between 2.9 ppb and 3.5 ppb
Step-by-step explanation:
You are given the total number of samples, the concentration of lead, and the standard deviation. The standard deviation represents how inaccurate the estimation of the concentration of lead in the drinking water. This means that there can only possibly be a 0.3 ppb error in the estimation. 3.2-0.3=2.9, and 3.2+0.3=3.5
Answer:
m
Step-by-step explanation:
Answer:
probability of landing on a number greater than 2 on the spinner.
Step-by-step explanation:
A theoretical probability is given by the number of desired outcomes divided by the number of total outcomes.
In this question:
8 possible outcomes(all numbers from 1 to 8).
6 desired outcomes(3, 4, 5, 6, 7 and 8, that is, all the numbers greater than 2). So

probability of landing on a number greater than 2 on the spinner.
330 miles / 5.5 hours
= 54.54 miles/hour.
Glad I could help!