Given a circle with radius of 2, which is the degree measure of an arc whose length is 1/2 pie ?

Formula to find the arc length is:

So, if we want to measure the central angle then it will be:

Where, s= arc length,

r = radius of the circle

= central angle in degrees.

According to the given problem, and r = 2.

So, first step is to plug in these values in the above formula.

π has been cancel out from both top and bottom.

=45

So, measure of central angle is 45°.

then, the surface area of the sphere shown in the image is: 256π sq. units!

step-by-step explanation:

the lateral surface area of a sphere is 2πrh where h=2r.

then:

surface area = 4πr^2.

in this case, r=8 units ⇒ surface area = 4π(8 units)^2. = 256π sq. units!

then, the surface area of the sphere shown in the image is: 256π sq. units!

a = 11 : 4

b = 38

c = 1 for every 6