Can someone tell me if this answer is right because i'm not too sure

Why do many scientists suppose the land bridge theory of migration?

What happened in the tinker v des monies? and why is it important what happened in the hazlewood v. kuhlmeier? why is it important?

According to us supporters, which was a benefit of purchasing alaska? the territory would be a buffer to invasions from europe. the territory would provide a place for many americans to live. it would increase trade by improving access to the northern pacific. it would increase the united states’ power by creating a bond with russia.