CONFUSED!!! Is a 7.9% APR with a 'Spread' of 3.9% equal to an Interest Rate APR of 11.8%?

Your agreement doesn't specify a rate; it is a variable rate card and it specifies a base rate plus a spread. So they calculated the 7.9% by adding 3.9% to whatever the base rate was (usually a published rate like the prime or a treasury bill rate)