Find the dimensions of a, b,c and d in v=root ab + bt + c/d+t

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

c) up is the direction the magnetic force is acting on the charge.