A 30.3kg girl and a 56.0kg boy are on the surface of a frozen lake, 15.0m apart. Using a rope, the girl exerts a horizontal 4.50N force on the boy, pulling him toward her. Calculate the magnitude of the girl's acceleration.
so for this problem i am just confused about the equation to use. i know that it will use a frictionless equation but that is about all that i am sure of.