I'm having trouble with the following problems: 1) A student throws a water balloon down at his math professor walking on the sidewalk. He drops a balloon from 18.0 meters above the ground when the profesor is 1.00 meter from the point directly beneath the window. IF the professor is 170 cm tall and walks at a rate of .450 m/s does the balloon hit her? If not, how close does it come? Given: height= 18 m, v (init)= 0, g= 9.8 m/s2 I dont know where to start after this though for I dont know how to figure out the velocity of the balloon! 2)A jet aircraft being launched from an aircraft carrier is accelerated from rest along a 94.0 m track for 2.5 sec. a) what is the acceleration of the aircraft, assuming its constant? and b) What is the launch speed of the jet? For this one I calculated part a: v= 94 m/2.5 sec = 37.6 m; a= 37.6m/2.5sec = 15 m/s2. However the back of the book states that the answer should be 30 m/s2. And I'm not sure how to go about calculating part b. Thanks for any help- i appreciate it!