Which would be needed to make a ball at the base of a ramp move up the ramp?

A. Inertia
B. Force
C. Gravity

I already canceled out gravity but im not sure about A and B..

What color would an object that reflects green and blue light appear to be in white light? a. blue b. cyan c. magenta d. black

At an oceanside nuclear power plant, seawater is used as part of the cooling system. this raises the temperature of the water that is discharged back into the ocean. the amount that the water temperature is raised has a uniform distribution over the interval from 10° to 25° c. what is the standard deviation of the temperature increase?

When using the scientist method, which step comes last?