Which form of birth control could people use without Internet and normal systems are blocking sperm from fertilizing an egg

Calculate the heat capacity per object when the total energy is 4 quanta. (think of this in terms of increasing from 3.5 quanta of energy in the system to 4.5 quanta of energy in the system, if that were possible.) c4 = __ j/k/object

Which type of wave can travel without a medium

Which diagram correctly demonstrates the various forces acting on a ball moving horizontally with some speed?