Answer:
22.5
Step-by-step explanation:
If you expand the series, you can see the first few terms of the series:
- Putting 1 in
, 
- Putting 2 in
, 
- Putting 3 in
,
- Putting 4 in
,
We can see the series is 0, 0.5, 1, 1.5, ....
This is an arithmetic series with common difference (the difference in 2 terms) 0.5 and first term 0.
We know formula for sum of arithmetic series:

Where,
denotes the nth partial sum
is the first term (in our case it is 0)
is the term (in our case it is 10 since we want to find 10th partial sum -- sum until first 10 terms)
is the common difference (difference in term and the previous term) (in our case it is 0.5)
Substituting these into the formula, we get the 10th partial sum to be:

So the sum of the first 10 terms is 22.5. Third answer choice is right.
I think it is the first and third one
Answer:
Hypothesis
Step-by-step explanation:
When people make researches, they make a statement and then go further to either price that statement wrong or right.
Once the statement is proven right, either by virtue of field work or laboratory work, it becomes a theory.
That unproven statement that can either be true or wrong, but baseless because it is yet to be proven is called HYPOTHESIS
Answer:
1/4
Step-by-step explanation:
I'm not sure if he wants the Dilution factor or the scale but anyway
CBA = 4 C'B'A'
Scale 1/4
Answer:
regular a polygon is: c, e, a
irregular is: b
not a polygon is f, d
Step-by-step explanation:
Regular is a normal shape which has angles
Irregular has straight lines all the way.
Not a polygon has not straight lines and sometimes has a gap in between the lines.
Hope this helps.