Average speed is found by simply dividing the distance travelled by the time that it took to finish the trip. It's measured in meters per second (m/s), so first convert the quantities.
1 km = 1000 m, so 16 km is 16000 m
0.25 hours is 15 minutes. Since 1 minute is 60 seconds, then 15 minutes must be 900 seconds.
Thus:
average speed = total distance/total time = 16000 m / 900 s = 17.78 m/s
Answer:Protons, neutrons, and electrons are the three main subatomic particles found in an atom. Protons have a positive (+) charge. An easy way to remember this is to remember that both proton and positive start with the letter "P." Neutrons have no electrical charge.