1) true
2) false
3) true
4) false
5) true
Answer:
The measure of the third arc is 
Step-by-step explanation:
step 1
we know that
The measurement of the external angle is the semi-difference of the arcs which comprises
in this problem
Let
x----> the greater arc of the circle intercepted by the secant and the tangent
y----> the smaller arc of the circle intercepted by the secant and the tangent

----> equation A

-----> equation B
Substitute equation B in equation A and solve for y

Find the value of x

step 2
Find the measure of the third arc
Let
z------> the measure of the third arc
we know that
-----> complete circle
substitute the values and solve for z


The axis of symmetry of a parabola in the form

is a vertical line

where k is the x coordinate of the vertex of the parabola.
The x coordinate of the vertex of the parabola is given by

which in your case is

So, the axis of symmetry is the line x=12.