1. An electric pump raise 9.1m^3 of water from a reservoir whose water-level is 4m below ground level to a storage tank above ground. If the discharge pipe outlet is 32m above ground and the operation takes 1hour,find the minimum power rating of the pump if it's efficiency is 70%.(1m^3 of water has a mass of 1000kg) 2. Relevant equations 3. The attempt at a solution An Idea suddenly came to me I need to find the energy but using Potential Energy formula? mgh? I'm sorry I have no Idea how to attempt it, please help me, give me a hint on what to do.