What conclusion can you draw from paragraph 6? Ham operators like to set set up up their equipment in parking lots.
Many car owners forget to change the batteries in their remote locking devices.
Radio signals can not penetrate glass doors.
Malfunctioning equipment can emit stray radio waves.

Occasionally ham operators are asked to solve down-to-earth mysteries. Remote locking devices for cars use radio waves. Outside one department store, shoppers discovered that their remote locking devices did not work. Ham operators were brought in. They walked around with hand-held antennas and a receiver. They discovered that strong stray radio signals emitted from the building interfered with the locking devices. Store personnel were alerted and repaired the offending equipment. By law, no one can transmit radio signals strong enough to interfere with other equipment nearby. Ham radio operators have fun in many ways!

The answer is frictional force

    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