The correct options are
A Floating of ships and submarines
B The lactometers to test purity of milk
Archimedes principle states that when a body is immersed partially or fully in a fluid, it experiences an upward force that is equal to the weight of the fluid displaced by it. The two applications of Archimedes principle are: (i) Floating of ships and submarines (ii) The lactometers to test the purity of milk.