What is ozone and how does it effect any ecosystem

Coquina, a type of limestone, forms from shell fragments that settle on the ocean floor. what type of rock is coquina?

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

Idon’t know the answer and i’ve been stuck on it for a while now skskskskks