1) Which command should be used to create a local copy of the repository https://github.com/marklee77/vpack.git in the directory "vectorpack"
a) git copy https://github.com/marklee77/vpack.git vectorpack
b) git copy vectorpack https://github.com/marklee77/vpack.git
c) git clone https://github.com/marklee77/vpack.git vectorpack
d) git clone vectorpack https://github.com/marklee77/vpack.git

2) Suppose that you create a fork of a repository to your account and modify your copy. Someone else sees your code on github and suggests that you submit a "pull request". What does this mean and why should you do it?