Just got done reading the chapter... Want to make sure I have this right....

IF Circumference = 2(pi)r

Let cir = 360 deg.

So that 360 deg = 2(pi)r

And 180 deg = (pi)r

IF r = 10

then 180 = (pi)10

Hence half of a cirlce with radius of 10 has an arc measure of 10(pi).....

Is this correct?

And if I wanted to find An arc measure of angle 70 deg I would

solve for x

180x = 70

x = 70/180 = 7/18

then

70 = (7/18)(Pi)(10)

If radius is 10....