What units are used when describing the length of time that the universe has been expanding? [check all that apply] [a is not the only answer]

billions of years
millions of years
light years
light year kilometers
decades

Billions of years, there isn’t anything else

the first phase of the government’s plan for settlement was building the transcontinental railroad. the railroad provided a way to bring settlers and manufactured goods west and ship their agricultural and mining produce east. the transcontinental railroad was an essential artery for rapid development of the frontier.

the second phase of the government’s plan was a liberal land distribution policy that made it possible for many people to homestead. with these two key elements—transportation and cheap land—the government rapidly achieved its goal of persuading people to move west, settle on farms, and push back the frontier.

the value of the 4 in the hundreds place is 400 while the value of th e 4 in the tens place is 40

400 is way bigger than 40.