Answer:
a. normal
Explanation:
In the field of physics the normal is a line drawn at a right angle to a barrier. In other words the normal line is the line that is drawn perpendicular (right angle, 90 degrees) to the reflective surface of a mirror, or the particular boundary in which refraction occurs at the point of incidence of a light ray. This can be seen in the picture attached below.
Number three
They contain protons (positive), neutrons (negative), electrons (neutral) and all are in a nucleus which is part of an atom
This would be an example of deposition (Phase transition).
Physical development , Cognitive Development , psychosocial development I think!
First:
d = 100 m
t = 200 sec
v = 100/200 = 0.5 m/s
Displacement is zero since he returned to his start point.
t2 = d/v2 = 100/2 = 50 sec
total time = 50 + 200 + 500 = 750 sec