Please help if you know the answer please

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

Describe two recent or ongoing space missions.

What condition is kept close to its set point in osmoregulation? a. body temperature b. platelet count c. blood glucose level d. water balance