data science and big data analytics

1.What is a logit and how do we compute class probabilities from the logit? 

2.Compare and contrast linear and logistic regression methods. 

3.Let x3 be the following vector:  

x3 <- c(0, 1, 1, 2, 2, 2, 3, 3, 4)

Imagine what a histogram of x3 would look like. Assume that the histogram has a bin width of 1. How many bars will the histogram have? Where will they appear? How high will each be?

When you are done, plot a histogram of x3 with bin width = 1, and see if you are right.