Stacy and Melissa work as waitresses. They both earn $7.75 per hour, plus tips. Last weekend, Stacy worked x number of hours and earned $153.95 in tips. Melissa worked y number of hours and earned $129.02 in tips. Stacy determined that using the expression 7.75x+153.95+7.75y+129.02 will calculate the amount the girls earned together last weekend. Select another expression the girls could also use.

a.7.75(x+y)+282.97
b.7.75(xy)+282.97
c.7.75x+y+282.97
d.7.75x+7.75y−282.97