Angle of elevation is angle measured from horizontal line to line of sight, The distance from the plane to the observer is 25,636 feet approx
<h3>What is angle of elevation?</h3>
You look straight parallel to ground. But when you have to watch something high, then you take your sight up by moving your head up. The angle from horizontal line to the point where you stopped your head is called angle of elevation. See the figure where angle OPD is the angle when observer saw the plane. It is measured from the horizontal line OD.
Refer to the attached figure.
It is given that we have
Length of PD = |PD| = 21,000 feet
Angle ∠OPD = 55°
Assuming length of OP = |OP| = x feet, we get the sin ratio as
(tan 55° was calculated from online calculator)
Thus,
The distance from the plane to the observer is 25,636 feet approx.
Learn more about trigonometric ratios here:
brainly.com/question/22599614
Answer:He averaged about 3 miles per day. Hope this helped ya have a nice day
Step-by-step explanation:
Answer:
36.58% probability that one of the devices fail
Step-by-step explanation:
For each device, there are only two possible outcomes. Either it fails, or it does not fail. The probability of a device failling is independent of other devices. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which 
is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
A total of 15 devices will be used.
This means that 
Assume that each device has a probability of 0.05 of failure during the course of the monitoring period.
This means that 
What is the probability that one of the devices fail?
This is 
36.58% probability that one of the devices fail
The answer would be B-D-F
0.02/ zero point zero two
