Challenge 1: "Write a script to calculate the value of e, also known
 as Euler's number and Napier's constant."

My notes: The associated wiki page reminds us that the easiest way of
  calculating e (the base of natural logarithms) is via:
  e = 2 + 1/2! + 1/3! + 1/4! + ... 1/n!  Let's use that.


Challenge 2: "Write a script for URL normalization based on rfc3986. This
task was shared by Anonymous Contributor.

According to Wikipedia, URL normalization is the process by which URLs
are modified and standardized in a consistent manner. The goal of the
normalization process is to transform a URL into a normalized URL so
it is possible to determine if two syntactically different URLs may
be equivalent.

My notes: The RFC link points to a long list of regex-syle changes,
not all of which have to be implemented.  Easy to implement most.