How to Bypass Proxy to Ping Google. Com in Terminal

I am trying to ping google.com in my ubuntu terminal. but getting an error message.

ping 
ping: unknown host 

I am behind the proxy of my university network. I have seen many examples on INTERNET of how to do this, but have none worked for me.

I am using UBUNTU 14.04 LTS (I am a new user of UBUNTU)

I have tried the following solutions

Option 1

gsettings set org.gnome.system.proxy mode 'manual'
gsettings set org.gnome.system.proxy.http enabled true
gsettings set org.gnome.system.proxy.http host '
gsettings set org.gnome.system.proxy.http port 3128
gsettings set org.gnome.system.proxy.http use-authentication true
gsettings set org.gnome.system.proxy.http authentication-user 'myusername'
gsettings set org.gnome.system.proxy.http authentication-password 'mypassword'

Finally

sudo gedit /etc/apt/apt.conf.d/20proxy

Acquire::http::Proxy ""

Option 2

sudo -H gedit /etc/profile.d/proxy.sh
export http_proxy= 
export ftp_proxy=
export telnet_proxy=

Unfortunately, neither of these worked.