Subject: How much physical space does a barrel of oil take, a ton of coal take?

I have to present a topic on the earth's crust and I wanted to say how much 
coal and oil is taken out of the earth's crust every year ... but a barrel of 
oil or a ton of coal doesn't mean very much to me ... I wanted to be able to 
say how much in terms of how many classrooms. I also wanted to say how many 
diamonds were taken out of the crust each year as well, and how much space 
that would take. I have found out lots of information on the internet but not 
the answers to these questions ... it would be great if you could help me. 
Thanks, Rhiannon

Re: How much physical space does a barrel of oil take, a ton of coal take?