Write code segments that perform the following tasks: a. Replace every blank space character in the string str with a newline character ('\n'). b. Find the index of the first instance of the substring...

Write code segments that perform the following tasks:

a. Replace every blank space character in the string str with a newline character ('\n').

b. Find the index of the first instance of the substring "the" in the string str.

c. Find the index of the first instance of the substring "the" after the midpoint of the string str.

d. Count the number of instances of the whole word "the" in the string str.