Answer:
B. 15/17
Explanation:
(see attached graphic for reference)
Because we have a right triangle (i.e one of the internal angles is 90 degrees), we can use trigonometry to solve
from the diagram, we can see that
cos 28° = adjacent length / hypotenuse
we can also see that the length adjacent to 28° = 15 units and the hypotenuse is 17 units,
hence, substituting these values into the equation:
cos 28° = 15 / 17 (answer)
edit: typo