The interactions of earthworms and robbins in a beach far is make up which ecological unit

The unit is called Ecosystem.

Ecological units comprise concepts such as population, community and ecosystem.

An ecosystem is a community of plans and animals interacting with each other in an particular area. They also interact with their non-living environments (water, earth, sun, soil, climate and atmosphere).

The robins are in relationship with the earthworms because the robins eat them in order to survive and as a part of the food chain. The food chain is a linear sequence of organism through which nutrients and energy pass as one organism eats another. Ecosystems consist of creatures that mutually benefit from each other.

s the president shall be commander in chief of the army and navy of the united states, and of the militia of the several states, when called into the actual service of the united states; he may require the opinion, in writing, of the principal officer in each of the executive departments. sooo yeahhh

explanation:

four sitting presidents have been assassinated while in office but the first was abraham lincoln,