The movement of the tectonic plates is caused by a) convection currents in earth's mantle. b) the gravity of the iron-nickel core. eliminate c) the rotation of the earth. d) the moho discontinuity.

Answer(b) both involve the use of levers;

Dust and gases contract.

The net force would equal 13 newtons , forward. the mass will accelerate. balanced forces: when forces are in balance, acceleration is zero. velocity is constant and there is no net or unbalanced force.hope this : )