The following assignment statements either contain at least one error, or could be improved in some way. Assume that radius is a variable that has been initialized. First, identify the problem, and then fix and/or improve them:

33 = number The variable is always on the left number = 33 my variable = 11.11; Spaces are not allowed in variable names my_variable = 11.11; area = 3.14 * radius^2; Using pi is more accurate than 3.14 area = pi * radius^2; x = 2 * 3.14 * radius; x is not a descriptive variable name circumference = 2 * pi * radius;