Answer:
A. Angle CAB and angle BCA
Step-by-step explanation:
Hope it helps you in your learning process.
I believe the answer will be t + 40 = race time
Answer: 88 years
Step-by-step explanation:
The mean of this test will be 57.
<h3>What is Standard Deviation and Mean?</h3>
A standard deviation (or σ) is a measure of how dispersed the data is in relation to the mean.
The mean can be used to get an overall idea, or picture, of the data set.
Let Mean be 'm'
and standard deviation= 
So, m-2
=49
and, m +
=61
Solving the above two equation we get

Now, m= 61-
= 61-4
= 57
So , the mean of this test will be =57
Learn more about mean and standard deviation here:
brainly.com/question/16030790
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