The atlantic ocean and the great lakes have different elevations. which two human made structures ships navigate through the sea way?

Locks and Canals

Explanation:

The Atlantic Ocean and the Great lakes have different elevations because of canals and locks that help in bringing ships to navigate through the seaway. The canal is human-made waterways that permit ships from both sides to enter and reduces the time of journey. The locks in canals help in altering the level of water of the canal by filling it up or decreasing it.

community or area create social relationships that typically differ greatly from the affiliations ultimate effects of travel experiences on the population in areas of origin, as well as in places of wage of only a dollar or two. motorcoach operators, museums, and restaurants fall into the broad category of public

explanation:

answer called a epicycle;