Why did native americans sign treaties forcing them onto reservations?

Need on these last 2 questions on my social studies homework 5 and 6 then i’m done with the homework

What were the purposes of salt? check all of the boxes that apply. -to achieve peace -to protect the security of the united states -to form an alliance against communist nations - to stop the nuclear arms race - to give the united states an advantage over the soviet union

What reason did yurovsky give nicholas ii for his pending execution? the czar’s relatives were about to rescue the romanovs. nicholas had committed crimes against the russians. nicholas had misused his power to abuse his own people. nicholas had not lived up to his duties as czar of russia. the answers are not b and c, i already tried those.