Answer:
B. 4200
Step-by-step explanation:
A suitable calculator can add the terms for you. (See attached)
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The first term is 69, and the common difference is 75-69 = 6. The general term is ...
an = a1 +d(n -1)
an = 69 +6(n -1)
Then the 28th term is ...
a28 = 69 +6(27) = 231
The average term is (a28 +a1)/2 = (231 +69)/2 = 150.
The sum is the number of terms multiplied by the average term:
sum = 28×150= 4200
<h3>
Answer: 
</h3>
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Explanation:
Both legs are the same length, as indicated by the tickmark.
- a =

- b =

- c = x
Use the pythagorean theorem to solve for x

<span>The answer is 60.
Explanation<span>:
In mathematics, the word "of" indicates multiply. This means we would multiply 2/3 * 90.
We can write 90 as a fraction by putting it over 1, which gives us 2/3(90/1).
To multiply fractions, we multiply straight across: (2*90)/(3*1) = 180/3 = 60.</span></span>