For each question, use appropriate command in matlab. Get a screenshot for the command and matlab result and paste it

1. Create a 4x4 matrix in matlab with variable name as A

2. Use appropriate matlab command to select column 4 of A.

3. Create a time vector from 0 to 20 with interval of 0.1

4. Create a sine wave using the time vector time vector in question 3, amplitude 3, frequency 5 and phase 45.