Answer:
1/6 has been vacummed.
Step-by-step explanation:
Hello!
The formula for circumference is

and the formula for area of a circle is

. Armed with these formulas, we can begin to find the circumferences and areas of the circles.
20.
C =

C =

C =

C = 13(3.14)
C = 40.8
A =

A =

A =

A = 132.7
The circumference of the circle is 40.8 in and the area of the circle is 132.7 in².21.
[Since we are given the diameter for this problem, to find the circumference, we no longer need to multiply the radius by 2 as in

because the diameter is the radius × 2. For

we do need to divide the diameter by 2.]
C =

C = 49.3
A =

A =

A =

A = 193.5
The circumference of the circle is 49.3 in and the area of the circle is 193.5 in².
And that is all there is to it. I hope this helps you! (:
The answer to number eight is
That it would have to reflect in the middle and it has Proportional angles.
Answer:
a. 5.25cm
b. 374.6 cm^2
Step-by-step explanation:
The radius of the conical cup is half the length of the arc formed
Mathematically, the length of the arc would be;
L = theta/360 * 2 * pi * r
L = 135/360 * 2 * 22/7 * 14 = 33 cm
Now, the arc of this sector will become the base circumference of the circular base of the cone
Thus;
2 * pi * R = 33
2 * 22/7 * R = 33
R = (7 * 33)/44 = 5.25 cm
b. The volume of the cone
Kindly note that the radius of the circle becomes the height of the cone
Mathematically;
V = 1/3 * pi * r^2 * h
Kindly note that the radius of the circle will become the slang height of the cone
We can use pythagoras’ theorem to find the height of the cone
Pythagoras theorem states that the square of the hypotenuse equals the sum of the squares of the two other sides
So here, slant height l is the hypotenuse, h and r are the other two sides
So 14^2 -5.25^2 = h^2
h^2 = 168.4375
h = 12.98 cm
Volume is thus ;
1/3 * pi * 5.25^2 * 12.98 = 374.6 cm^3