Final answer:
The rocks found in the Interior Plains of Saskatchewan and Manitoba are primarily sedimentary rocks.
Step-by-step explanation:
The rocks found in the Interior Plains of Saskatchewan and Manitoba are primarily sedimentary rocks.
Sedimentary rocks are formed from the accumulation and lithification of sediments, such as sand, mud, and fossils, that have been deposited by water, wind, or ice. Examples of sedimentary rocks include sandstone, shale, and limestone.
Igneous and metamorphic rocks may also be found in the Interior Plains but they are less common compared to sedimentary rocks.