How would one be able to travel in time?

What color of light must blue light mix with to create white light? a. yellow b. white c. blue d. green

The boy of mass 30 kg is at r1= 2 meters from the fulcrum. of the girl is 45 kg, at what r2 must she sit so that they are balanced ?

In a system with only a single force acting upon a body, what is the relationship between the change in kinetic energy and the work done by the force? answers: work is equal to the change in kinetic energy.work depends on the square of the change in potential energy.work is equal to the negative of the change in kinetic energy.work is equal to the square of the change in kinetic energy