An object of mass 12kg is held at a height of 5 meters above the ground for 30 second's. The work done within this period is:

think its the third option

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.

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it