Options:
A. π is the area of a circle with a radius of 1.
B. π is the circumference of a circle with a radius of 1.
C. π is the constant of proportionality relating the radius of a circle to its area.
D. π is the circumference of a circle with a diameter of 1.
E. π is the constant of proportionality relating the diameter of a circle to its circumference.
Answer:
A, C, D, E
Step-by-step explanation:
Analyzing the options, one after the other.
A.
Area is calculated as thus:
[tex]Area = \pi r^2[/tex]
In this case,
[tex]r = 1[/tex]
So: we have
[tex]Area = \pi * 1^2[/tex]
[tex]Area = \pi * 1[/tex]
[tex]Area = \pi[/tex]
This option is true
B.
Circumference is calculated as thus:
[tex]C = 2\pi r[/tex]
In this case
[tex]r = 1[/tex]
So, we have:
[tex]C = 2\pi * 1[/tex]
[tex]C = 2\pi[/tex]
This option is false
C.
Area is calculated as thus:
[tex]Area = \pi r^2[/tex]
In this formula, Area and Radius can change but [tex]\pi[/tex] remains constant.
Hence, this option is true
D.
Circumference is calculated as thus:
[tex]C = 2\pi r[/tex] or [tex]C = \pi d[/tex]
Where [tex]d = diameter[/tex]
In this case
[tex]d = 1[/tex]
So, we have:
[tex]C = \pi * 1[/tex]
[tex]C = \pi[/tex]
Hence, this option is true
E.
Circumference is calculated as thus:
[tex]C = 2\pi r[/tex] or [tex]C = \pi d[/tex]
Where [tex]d = diameter[/tex]
Considering
[tex]C = \pi d[/tex]
In this formula, Circumference and Diameter can change but [tex]\pi[/tex] remains constant.
Hence, this option is true