A
because waves need air or something else to travel through
Buhrs atomic model differed from ruthofords because it explained that electrons exist in specified energy levels surrounding the nucleus. This means that, Ruthoford believed that electrons can't do very much. However, Buhrs' model showed that electrons are much more powerful than anyone else believes they can be.
Final speed = initial speed + (acceleration x time)
(final speed - initial speed) = acceleration x time
Time = (final speed - initial speed) / acceleration
Weight = mass * gravity = 60 kg * 3.75 m/s² = 225 N
<span>Option D.</span>
