Frank A. answered 11/03/20
Knowledge, experience and insight from decades of teaching physics.
Since mass of cart is 5.32, its weight is 5.32 x 9.81N
The component of weight acting down the slope is 5.32 x 9.81 x cos(-28.7°) = 45.78N
In addition, the cart is pushed down the slope with a force of 12.7N and is impeded by a frictional force of 8.33N
∴ net force on the cart is 45.78 + 12.7-8.33 = 50.15N
a = F/m ∴ a = 50.15/5.32 = 9.43 m/s2
Mr. A