To solve all of these, you put the expressions you've been given into an equation that equals whatever number the sheet tells you is the sum of the angle measures. Then you just substitute it in to find the angle measures. I'll do the first one for you but tell me if you want me to do the rest:
2k + k + 45 = 180
3k + 45 = 180
- 45
3k = 135
÷ 3
k = 45°
45 × 2 (2k) = 90
Again let me know if you want the answers and working to the other two :)