You will use the following facts:
1) The corner has 90 degrees
2) A straight line has 180 degrees
3) A full circle is 360 degrees.
Using the above facts gives you:
t = 90 degrees (remember to add 5 when checking)
x = 45 degrees
n = 60 degrees
p = 75 degrees
m = 30 degrees
s = 15 degrees
k = 135 degrees
w = 25 degrees
f = 65 degrees
y = 40 degrees
If you have any questions, let me know.
