The United States decides it wants to encourage citizens to buy televisions that are made in America so it decides to set a limit on the number of televisions that can be imported from China and Japan. This limit is an example of

Adjacent angles add up to 180° so angle a and the one labeled 75° add up to 180
So we do 180-75=105
a=105°

Vertical angles are congruent, so b and 75° are congruent.
so b=75°

Angles a and c are congruent, we know angle a is 105
so angle c=105°

Corresponding angles are also congruent, angles a and e are congruent
so angle e=105°

Angle 75° and d are also corresponding angles
so angle d=75°

Angles b and f are corresponding angles
so f=75°

And angles c and g are corresponding angles
so g=105°