Respuesta :

Given diameter 2cm
Find the area of a circle 
the formula for area of a circle 
A = pi r^2
the diameter is the radius times two 
so to find the radius given the diameter 2/2 = 1
radius is 1cm
pi is ~3.14
A = (3.14) * (1)^2
A = (3.14) * 1
A = 3.14

Hope this helps :)