(Data science and visualisation)

Create a vector z as (3, -6, 7, 8); Create x as 10. Find z*x

Create a list as (3, z, hello)

Create a matrix as

Create a data frame for the following data. The variable starting date can be a character variable.

Name	Salary	Starting date
John	21000	2010-11-01
Peter	23400	2008-02-15
Julie	26800	2007-12-11

Add a row of Mary with salary of $50000, starting date of 2009-11-1 to the data frame in previous activity

Add a column of gender to the above date frame (assign gender according to the names)