See the picture attached to better understand the problem
we know that
in the right triangle ABC
sin 70°=opposite side angle 70°/hypotenuse
in this problem
opposite side angle 70°=AB
hypotenuse=AC----> 32 ft
sin 70°=AB/32------> AB=32*sin 70°-----> AB=30.07 ----> AB=30.1 ft
we know that
in the right triangle ABC
sin 70°=opposite side angle 70°/hypotenuse
in this problem
opposite side angle 70°=AB
hypotenuse=AC----> 32 ft
sin 70°=AB/32------> AB=32*sin 70°-----> AB=30.07 ----> AB=30.1 ft