Answer:
-675
Step-by-step explanation:
The sum can be broken into parts that you know. Here, one of those parts is the sum of numbers 1 to n. That sum is given by n(n+1)/2.

__
Another way to do this is to realize the sequence of numbers is an arithmetic sequence with a first term of 65 and a last term of 67-2·75 = -83.
The sum of an arithmetic sequence is found by multiplying the number of terms by their average value. Their average value is the average of the first and last terms.
The average value of those 75 terms is (65 +(-83))/2 = -9, so their sum is ...
75(-9) = -675
Answer:
idk a or c
Step-by-step explanation:
The number (7×100)+(4×1/100)+(8×1/1,000) in standard form is 7.0048 × 10²
<h3>How to write number in standard form?</h3>
The number can be represented in standard form as follows:
(7 × 100) + (4 × 1/100)+(8 × 1/1,000)
Therefore,
7 × 100 = 700 = 7 × 10²
4 × 1/100 = 4 × 10⁻²
8 × 1/1,000 = 8 × 10⁻³
Therefore,
7 × 10² + 4 × 10⁻² + 8 × 10⁻³ = 700.048 = 7.0048 × 10²
learn more on standard form here: brainly.com/question/22649174
#SPJ1
49 is a composite number, which means it is divisible by 1, 7, and 49. Hope this helps! :)