If an object has 110 J of potential energy when it is 40 m off the ground, what is it’s potential energy when it is 200 m off the ground

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

Which of the following types of electromagnetic radiation has the longest wavelength? a. infrared light b. visible light c. ultraviolet light d. microwaves

Scientists follow specific processes in order to determine valid explanations and conclusions from observations. david observed strange lights in the sky above his home outside of roswell, new mexico. the only explanation that makes sense to him is that there are ufos in the area. what should david do next to verify his explanation?