Dual coding theory!!!!!!!!!!!!!?

Hey guys i have to write up and exp. We did an exp about imagery and memory. We used the imagery process to c if it would help us remember concrete and abstract words. We also used the rehearsal processto c if it would help us to remember concrete and abstract words. Now in order for me to start to write up the exp i need to know what are the 2 independant variables. I can't really figure out what they r cause in all my other exp there have only been 1 IP variable. Can u guys tell me what they r? and what the dependant variables are plz. Can u tell me y as well. I know what an IP and D vairable is i just can;t seem to figure this one out.