What happened during Christopher Columbus's voyage in 1492?

Drastic boundary changes can occur for all of the following reasons except for a. a shift in the way a river flows b. the collapse of a government system c. a conflict between two neighboring groups d. one country's decision to sell land to another country select the best answer from the choices provide

Sandstones that form in aeolian (wind/desert) environments appear very different from other sandstones, such as those formed in a beach/ shoreline environment and in rivers on land. give three identifying properties for each of the three sandstones that would tell a geologist which depositional environment they formed in. consider things such as the relationship between transportation and grain size, shape, roundness, sorting, fossils and composition.

Sarah is making a scale drawing of a painting that is 48inches wide by 120 inches high her paper is 12 inches wide and 24 inches tall she decides to use a scale 1 inches equals 4 inches is this a reasonable scale