Small circular rna molecules that infect plants and disrupt their growth

Environmental differences within ecosystems are generally caused by

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

Plz ! what does it mean for an allele to be dominant?