When the moon orbits the Earth, what two things are involved in keeping it there?

What are the four basic classes of organic molecules how do they differ structurally and functionally

Select the situation bellow that would produce a total displacement of zero. a. a trip to the moon and then to mars b. a horse galloping from one end of a field to another c. the criss-crossing path of a bug as it flies from flower to flower d.a round-trip ride to school and back

What is the next step in muscle contraction after the actin changes shape? (apex)