How did the completion of the transcontinental railroad change the lives of American citizens? It increased the wealth of all Americans and enabled them to travel more. It made cross-country travel too expensive for ordinary Americans. It decreased the safety of Americans who moved to settle the plains. It shortened travel time between the East and West for all Americans.

b.europe i believe because north america has 3 countries in a way and with all the stuff with illegal immagrants from mexico or whatever so i would say europe.

the correct answer is

d) rocket launcher

offline recommendation systems option b

because recommendation systems produce a list of two ways

1. through collaborative filtering

or

2. through content-based filtering

the award is named for an american naval historian and theorist, rear admiral alfred thayer mahan, united states navy who, through his writing, provided stimulus and guidance to those who share in the defense of the nation.