Hopefully I can get these sorted before my test, thanks for the help.

[sub] means that what ever follows it is a subscript

In base 10 a number (d[sub]n-1, ... , d[sub]1, d[sub]0)[sub]10 is even if and only if it's 'ones' digit, d[sub]0, represents an even number. Show that this statement is still true when ten is replaced by any even base b= 2k, k is an element of N

Proof 2...

Show that, in an odd base b = 2k + 1, k is an element of N, a number (d[sub]n-1, ... , d[sub]1, d[sub]0)[sub]b is even iff an even number of its digits are odd.

a little explanation would be cool, always get these types of questions wrong