Answer:
angle 1= 110 degrees
Step-by-step explanation:
A line = 180 degrees
Since angle 1 and 4 make a line then both of them have to equal 180 degrees.
So, you would just subtract 180-70(angle 4)= 110 which gives you angle 1.
You could do the same with angle 4 and 3, angle 3 and 2, and angle 2 and 1 since they all form a line.