I think we need to divide some numbers there
<span>This question can not be answered because the horizontal distance covered is not specified.</span>
Answer:
The probability that a call last between 4.2 and 4.9 minutes is 0.4599
Step-by-step explanation:
Let X be the length in minutes of a random phone call. X is a normal distribution with mean λ=4.2 and standard deviation σ=0.4. We want to know P(4.2 < X < 4.9). In order to make computations, we will use W, the standarization of X, given by the following formula

We will use
, the cummulative distribution function of W. The values of
are well known and the can be found in the attached file

We conclude that the probability that a call last between 4.2 and 4.9 minutes is 0.4599
The equation of the graph is given by y = cos(0.4x) and has an amplitude of 1
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
Since the curve crosses the y-axis at y = 1, hence it is a cosine graph. It has a maximum of 1 and a minimum of negative 1, therefore the amplitude is 1
Also, the angular frequency = 2π * 1/5π = 0.4
The equation of the graph is given by y = cos(0.4x) and has an amplitude of 1
Find out more on equation at: brainly.com/question/2972832
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Answer:7777
Step-by-step explanation: