Answer:
d. 20+10+5+2.5+...
Step-by-step explanation:
No geometric series with a common ratio of magnitude greater than 1 will have a finite sum. Nor will any arithmetic series.
Those descriptions exclude answer choices a, b, c. Choice d is a geometric series with a common ratio of 1/2, so will have a finite sum. (It is 40.)
Check the picture below.
notice that 146° is sitting on a flat-line, and thus it has a sibling linear angle, namely 34°.
now, recalling that a triangle has a sum of 180° for all interior angles, the missing one is 126°, and incidentally that is a corresponding angle with "c".