3. Scientists believe ____ these settlers crossed the Bering Strait in the Arctic to America by means of a land bridge. 4. There is still a strong Spanish influence in California. That is ____ today over 40% of Californians speak Spanish as a first or second language. 5. It is believed ____ before long the mix of nationalities will be so great that there will be no distinct major racial or cultural groups.

that

why

that