29°
triangles can only have 180°
This is a right triangle, so one angle is 90°, leaving us with 90° left
90°-61°= 29°
The coefficients would be 6 and 2.
Coefficient of k would be 6 and for n it would be 2.
B is the answer to the question
-0.9 as a fraction in simplest form is -

Hope this helps :)