Kristen purchased 2 binders that cost $1.25 each, 2 binders that cost $4.75 each, 2 packages of paper that cost $1.50 per package, 4 blue pens that cost $1.15 each, and 4 pencils that cost $0.35 each. a. write an expression to represent the total cost of supplies before tax. b. what was the total cost of supplies before tax?