## Assignment 1, Due Thursday September 13, 4pm

A1.1 Write a Python program to print `Hello World!'.

A1.2 Write a Python program that reads and inverts a string.

A1.3 Write a Python program to plot a multivariate Gaussian with a covariance matrix that has off-diagonal elements which are half the value of the on-diagonal elements.

A1.4 Write a Python program with a function that takes two arrays, *a* and *b*, and calculates the matrix *a***b*'**2 +*b*.

A1.5 Calculate the gradient of a two dimensional Gaussian and find the minimum.