A shopper is pushing a cart as shown. He applies a force of 15N at 12 degrees below the horizontal. Friction between the wheels and the ground is 2.8 N. If the weight of the cart and groceries is 19kg, what is the acceleration of the cart.

F= 15 N at 12°
Fr = Frictional force = 2.8 N
mass = 19 kg
a = ?
∑F=m*a
∑F= Fx - Fr
Fx = 15* cos 12
15 * cos 12 - Fr = 19 *a
Solve for a:
(15*cos12 - 2.8 )/19 = a
a = 0.62 m/s^2