(1) Most people borrow books once, accounting for 42%. People who borrowed books five times or more were the least, accounting for 3%.

(2) 4% borrowed it four times, 3% borrowed it more than four times and 7% borrowed it. All percentages are equal to 42%+10%+8%+4%+3%+33% =100% =1.

(3) look at the picture. One hundred percent.