Answer:
Correct choice is A
Step-by-step explanation:
Note that the denominator
Then rewrite the numerator
as 
Substitute both expression into the initial expression:

The whole angle is 90 degrees and you have 45 so 90-45 = your answer :)
2.5 mins. time is equal to distance divided by the speed. so 17.5 divided by 7 is 2.5
Given:
The sequence is
1, 2, 4, 8, 16, ...
To find:
Whether the given sequence is arithmetic or not. If yes, then find the common difference.
Solution:
We have,
1, 2, 4, 8, 16, ...
Difference between consecutive terms are



Similarly,



Since,
, therefore the given sequence have no common difference between consecutive terms.
So, the given sequence is not arithmetic.
Therefore, the correct option is c.