I think is 3.5 pretty sure
<span>Kinetic energy is a body that possesses by
virtue of being in motion. While potential energy possesses a body by virtue of
its position relative to others, stresses within itself, electric charge, and
other factors. As the “car” moves along the track its kinetic energy coverts to
potential energy when it moves up or down one of the hills. With the initial motion
already pushing it when it reaches a slope or dip it uses its own motion to
move along the track. </span>
<span>For
my track I used cardboard and for my “car” I used a spool of thread. The weight
of the cardboard is about .13 kg and the spool is about 0.9</span>
<span>P.s. these were my answers and I got a pretty good grade, for the weight of the track and "car" I did estimate it.</span>
Answer D
In alkali earth metals reacrivity increases from top to bottom (opposite of b)
This is because as you go down, the electron shells increase by 1 shell. The farther away a shell is from the nucleus, the higher its tendency to react.
D is true because the more reactive an alkali metal is, the more vigorous the reaction will be with water.