Replication refers to
a. doing your own experiment again
b. other scientists doing your experiment
c. writing down a clear step-by-step procedure
d. sharing information between different scientists

Around faucet handle is part of a(n) a. lever b. screw c. inclined plane d. wheel and axle

Can anybody me with this? ? (picture included.)

Abumper car with a mass of 250 kg is traveling at a speed of 4 m/s. this bumper car collides and sticks to a second bumper car with a mass of 250 kg, which is initially at rest. what is the final speed of these two bumper cars after the collision, assuming they remain stuck together?