What is the longest river in the usa

Which of there factors contributed most to us westward expansion in the second half of the nineteenth century?

8. is a technique that uses the images from several telescopes to produce a single image. a. reflection b. interferometry c. radiation d. refraction

If u make mistakes on a school trip to knotts like standing up on a ride too early and they ask you not to do it again or and if you do it again you will be escorted out will it go on my student record? yes i know it is a dumb question