Think its Positive
hope this helpes
D. Speed and direction, this is because velocity is a vector quantity so has a magnitude and direction assigned to it because it is the rate of change of displacement.
<span>Suppose you mixed two chemicals in the lab until you could not tell the two apart. After some time passed, a white powder formed which would not dissolve, and settled on the bottom. The mixture was first homogeneous then heterogeneous. </span>
Answer:
about 602 milliseconds
Explanation:
The motion can be approximated by the equation ...
y = -4.9t^2 -22.8t +15.5
where t is the time since the arrow was released, and y is the distance above the ground.
When y=0, the arrow has hit the ground.
Using the quadratic formula, we find ...
t = (-(-22.8) ± √((-22.8)^2 -4(-4.9)(15.5)))/(2(-4.9))
= (22.8 ± √823.64)/(-9.8)
The positive solution is ...
t ≈ 0.60195193
It takes about 602 milliseconds for the arrow to reach the ground.
B. five electrons
If you want an explanation, here it is.
The atomic number gives the number of protons. Protons which have a positive charge are balanced by an equal number of electrons in a neutral atom. Boron number 5 has five protons and therefore as a neutral atom also has five electrons.