1 Problem 1 : Matplotplib - Introduction ( https://www.geeksforgeeks.org/python-introduction-matplotlib/ )
2 Problem 2 : Pyplot in Matplotplib ( https://www.geeksforgeeks.org/python-introduction-matplotlib/ )
3 Problem 3 : Matplotplib - Axes Classes Matplotlib1 30 https://www.geeksforgeeks.org/matplotlib-axes-class/ )
4 Problem 4 : Multiple Subplots Matplotlib1 30 https://www.geeksforgeeks.org/how-to-create-multiple-subplots-in-matplotlib-in-python/