The file beer.txt contains two named columns Time (month) and Sales (numerical). Read the following Python program:

[1] import pandas as pd

[2] import matplotlib.pyplot as plt

[3] import numpy as np

[4] beer = pd.read csv(beer.txt )

[5] sales = beer[Sales ]

[6] sales_v = sales.values

Please answer the following questions: (a) What is the purpose of the first three lines [1], [2] and [3] in the program above? (b) Explain the meaning of line [4] in the program. What is the data type for variable beer? (c) What is the data type of the variable sales_v in line [6]?