What molecules are closely related to lipids? explain your answer.
a) sugars
b) long chains of carbon and hydrogen
c) amino acids
d) nucleotides

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