1. The problem statement, all variables and given/known data A cannon is shooting emergency packets to people stranded on the roof of a flooded building of height H = 106 meters relative to the cannon, the corner of which is located a distance D = 52 meters from the cannon. It is desired that the incoming packets are flying tangent to the roof as shown so that they land gently with as little impact as possible and slide along to a stop. Find the initial speed v_0 and at what angle theta (in radians) the cannon should be aimed to achieve the above scenario. 2. Relevant equations y=ax^2+bx+c 3. The attempt at a solution I created a parabola in the form of y=ax^2+bx+c that goes through the points (0,0) and (52,106) with a=-4.9 (2nd derivative is acceleration) and then finding b using the first derivative getting b=v=256.838, but this isn't the right answer. Could anyone please tell me what I am doing wrong and how to fix it. Thanks!