When does a mutation have the most impact on allele frequency?

Apart of an ecosystem that can restrict the growth of a population is referred to as

Ais a landform that is formed at the mouth of a river from the deposition of sediment carried by the river as the water flows.

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