Rutherford proposed

a) the atom is mostly solid space

b) the electrons are spread through a solid, positive nucleus

c) electrons are located surrounding a nucleus

d) atoms are the smallest particles of matter

It is B because when he made the rays go through the atoms, a very small little of it created a repulsion which resulted in him proposing that there is a dense, positive nucleus in the atom while electrons are spinning around. 

Velocity is the speed of an object in a certain direction so you'd need to know speed and direction