What is another way of naming ray a b ?

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Tabby sells clothing at a retail store, and she earns a commission of 6.25% on all items she sells. last week she sold a pair of jeans for $32.50, a skirt for $18.95, and 2 blouses for $14.95 each. what was tabby's total commission? a $4.15 b $5.08 c $81.35 d $348.60

Janice determined there were 10 possible outcomes when tossing two coins and spinning a spinner numbered 1 through 6. what is the correct number? what might have been janice's error?