Bacteria live in groups called colonies. colonies are usually circular. the diameter of a particular bacterial colony is 12 mm. the circumference of a circle is equal to pi (3.14) times the diameter (c = pi times the diameter)
1.what is the circumference of the colony?
2.what is the radius of the colony

the circumference is

3.14 times the diameter or

3.14 x d

since d is 8 the equation becomes

3.14 x 8 = 25.12 mm in circumference.

Explanation:

for example, no new evidence will demonstrate that the earth does not orbit around the sun (heliocentric theory), or that living things are not made of cells (cell theory), that matter is not composed of atoms, or that the surface of the earth is not divided into solid plates that have moved over geological timescales .