Which quantity is the vector?
a) weight
b) power
c) kinetiic energy
d) speed

D Speed

Explanation:

Vector, in physics, a quantity that has both magnitude and direction. It is typically represented by an arrow whose direction is the same as that of the quantity and whose length is proportional to the quantity's magnitude. Although a vector has magnitude and direction, it does not have position

a.   mass number from atomic number