The basic unit of length in the si measurment system is the

Which statement is true? a. kepler's laws apply only to the motion of earth. b. kepler's laws can be used to predict eclipses. c. kepler's laws are true for a central force that is directly proportional to distance. d. kepler's laws can be deduced from newton's laws of motion and gravity.

1kg of water needs to recieve 4200j of energy to go from 90 degrees to 91 degrees. what is the specific heat capacity of water? what are the units?

An element becomes a positively charged ion when itloses protons.loses electrons.gains electrons.gains neutrons.