A- 5.57
B- 41
C-12
D-21.71

Step-by-step explanation:

If KM bisects angle NKL, the angle 3 is congruent to angle 4.  

We are given that angle 1 is congruent to angle 2, so that means that angle JKP is congruent to angle PKN.  By the definition of an angle bisector, we know then that angle NKM is congruent to angle MKL.  By the definition of a straight angle formed by opposite rays, all those angles named above add up to equal 180 degrees.  So if angle JKN = 8x + 2 and angle MKL = 3x + 5 and angles NKM and MKL are congruent, then angle NKL = 2(3x + 5) which is 6x + 10.  Again, if all those angles above add up to equal 180, then

8x + 2 + 6x + 10 = 180 and

14x + 12 = 180 and

14x = 168 so

x = 12.

Angle MKN = 3x + 5 so if x = 12, then

Angle MKN = 3(12) + 5 and

Angle MKN = 41 degrees