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:
1.) - 2
2.) - 72
Step-by-step explanation:
hope this helps
9514 1404 393
Answer:
21.25 seconds
Step-by-step explanation:
In miles per second, the speed of the jet is ...
(720 mi/h)/(3600 s/h) = 1/5 mi/s
The speed of the sound is the same:
(1 mi)/(5 s) = 1/5 mi/s
Then the rate of closure between the airplane and the sound is ...
(1/5 mi/s) +(1/5 mi/s) = 2/5 mi/s
To find the time required to close a gap of 8 1/2 miles, we can use the relation ...
time = distance/speed
time = (8.5 mi)/(0.4 mi/s) = 21.25 s
The pilot will hear the thunder 21.25 seconds after the flash.
Answer:
(7) = 175
Step-by-step explanation:
hope this helps! just follow the order of operations. :)
The answer would be D. In an inverse function, the x and y vlaues are switched (not in order though!).
