Mini water rocket

SPECIFICATIONSBrand Name: GJCUTEMaterial: PlasticOrigin: Mainland ChinaRecommend Age: 4-6yThis amazing little rocket uses pressurized water to blast off.  You fill up the rocket with water, pressurize the tank by pumping it up with air from a bike pump (included), and then step on the pedal to launch the rocket.  This rocket is small, but it still packs some punch.  Don't be surprised if it goes 30-40 feet into the air.  This is hours of fun and a great way into the math of rocketry.  Some interesting measurements to look at while you play: You can measure the weight of the empty rocket before filling the tank. You can measure the payload (water weight), and the flight time to apex to estimate the average lb/sec thrust being generated. You can measure the number of pumps you use with each launch. If you are measuring, you might as well make some hypothesis (educated guesses) If only put a little water in, and then vary the number of pumps.  How does the pressure affect the f