1) Declare an array containing a list of numbers. Write code that produces the sum of the numbers. Determine the maximum value in the list. 

2) Take the list defined in 1) and transform it into another list containing the squares of the values. Implement this using the foreach method and again using the map function.

3) Define a string containing a sentence of English text (several words with spaces). Replace the spaces with commas. 

4) Take a string with a DNA sequence. Split it into the different bases as an array. Count the number of different nucleotides.

5) Read strings from STDIN (using a while(){} loop) and add the entered text to a list. Return the items in reverse order. Return the items sorted. Return the total number of characters in the list.

5) Declare a hash with countries as the hash key and capitals as the hash value. Write a small script that lists the countries in alphabetical order along with their capitals.