A 350-kg box is pulled 5.10 m up a 23.0' inclined plane by an external force of 5000 N that acts parallel to the frictionless plane. 1) Calculate the work done by the external force. (Express your answer to two significant figures.) K.J Submit 2) Calculate the work done by gravity. (Express your answer to two significant figures.) k.J Submit +) 3) Calculate the work done by the normal force. (Express your answer to two significant figures.) Submit 4) The box started at rest. What is its velocity after it travels the whole 5.10 m length on the incline? (Express your answer to two significant figures.) m/s Submit +)