In the early 1800s, british engineer richard trevithick invented the first railway steam locomotive. by 1850, britain had more than 6,000 miles of railroad track. these two events are an example of which type of relationship?

Causation

Explanation:

A causal relation is one that represents two events, where the second event was caused by the first event. In the case of the text shown in the question, the miles of railroad track, were built because previously the first railway steam locomotive was created.

2686-2181 bce-- "egyptian civilization developed along the nile river in large part because the river’s annual flooding ensured reliable, rich soil for growing crops."

1069-664 bce-- "ancient egyptians developed wide-reaching trade networks along the nile, in the red sea, and in the near east."

yup! you are correct it is b.