Help please its science exam

What object a collides with object b and bounces back its final momentum is?

What pressure difference is required between the ends of a 2.0-m-long, 1.0-mm-diameter horizontal tube for 40 c water to flow through it at an average speed of 4.0 m/s?

Your science teacher brings in a speaker to talk to your class about climate change. during the session, students ask a few questions. which questions are related to the current evidence on climate change