1. A brick is thrown upward from the top of a building at an angle of 25o to the horizontal and with an initial speed of 15 m/s. The brick hits the ground after 3.0 s of flight. (a) Calculate the height of the building. [Label all kinematics charts clearly.] (b) Suggest what kind of building this might be, and whether this brick was thrown by hand or with a brick cannon. Justify your answer as you would to a non-physicist. (c) State the magnitude and direction of the brick’s velocity and acceleration vectors at the instant after the brick was released. Justify your answers. (d) State the magnitude and direction of the brick’s velocity and acceleration vectors at the instant when the brick was at the highest point of its flight. Justify your answers. (e) State the magnitude and direction of the brick’s velocity and acceleration vectors at the instant immediately before the brick hit the ground. Justify your answers.

    m₁v₁ + m₂v₂ = (m₁ + m₂)vmomentum is conserved.the left-hand side of the equation represents the momentum in the system before the collision.the right-hand side represents the momentum in the system after the collisionm₁ and v₁ represents the mass and the velocity of the physics blockm₂ and v₂ represents the mass and velocity of the ball of puttyv represents the final velocity of the combined mass.the question states the two masses stick together. they combined mass has its own velocity with the body mass the sum of the two objects' massestheir combined momentum is (m₁ + m₂)vto find the magitude of (m₁ + m₂)v, we need to add the vectors on the left-hand side of the equation: m₁v₁ + m₂v₂.note the diagram. i have positioned the vectors in accordance with their directions.the magnitude of the resultant can be calculated using the pythagorean theorem since this is a right triangle situation (north and west are perpendicular)|(m₁ + m₂)v| =  √[ (m₁v₁)² + (m₂v₂)² ]|(m₁ + m₂)v| =  √[ (1.5kg·8.0m/s)² + (0.40kg·20m/s)² ]|(m₁ + m₂)v| =  14.4 kg m/sfor two significant figures (assuming that 20m/s is two), this rounds to 14 kg m/s

Ithink it is a. but i'm not 100 percent sure.