At the top it says mandy answered four times as many questions as erica during the math race

The first, second, and third choices are correct; if Mandy answered times as much as Erica, then the number of questions Erica answered times is equivalent to Mandy's number of answers. Likewise, the number of Mandy's answers divided by is also equivalent to Erica's number. If solved, using the value given for ,  and  ÷ both result in , thus making the third choice true.

(-14+3/2b) - (1+8/2b) = -5 -5/2b(-10+b) + (7b-5) = 8b-15(7/2b-3) - (8+6b) = -5/2b-11(5+2b) + (2b+3/2) = 4b+ 13/2