arc length along x-axis

Move the green point to form a central angle of 1 radian. Given that the radius = 4 ft, what is the length of segment p in feet?

1 ft No Idea! 1 radian 4 ft

Move the green point to form a central angle of 2 radians. What is the length of segment p?

8 ft 1 radian 2 radians 4 ft

Move the green point to form a central angle [math]\pi[/math] radians. What is the length of segment p?

1 ft [math]\pi[/math] ft [math]4\pi[/math] ft

Move the green point to form a central angle 5 radians. What is the length of segment p?

5 ft [math]5\pi[/math] ft cannot tell from info give. 20 ft

Information: arc length along x-axis