-5. Hope this helps you out!
Simple, multiply.
3/8*2/7
You can cross cancel the 2 and the 8, making them into a 1 and 4.
Making it,
3/4*1/7
Multiply,
3/28. This can't be simplified further; thus, 3/28 is your answer.
Angle B is the linear pairs with 60°, so the size is 180-60=120°
Angle ABC is the linear pair with 120°, so the size is 180-120-60°
Angle A corresponds to angle 60°, so they are equal
Angle BAC is the linear pair with angle A and angle 70°, so 180-(60+70)=50°
Angle ACB is 180-(50+60) = 70°