Create a new environment called multiples_of_pi. Assign these objects into it:

• two_pi with the value 2 * pi, using double square brackets
• three_pi with the value 3 * pi, using the dollar sign operator
• four_pi with the value 4 * pi, using the assign() function

List the contents of this environment along with their values (no need to store this in an object).

(from: Cotton, 2013, Learning R, O’Reilly)