What are some of the reasons Russia has had problems instituting effective economic reforms since the end of the Soviet Union?

Review the statement. after the spanish-american war, the united states gained control of samoa, guam, and puerto rico. which options most accurately analyze how this expansion transformed the united states? (select all that apply.) a. it prevented the united states from developing its economic might. b. it allowed the united states to establish a military presence abroad. c. it established its presence on the world stage as an imperial power. d. it led to an increase in tension between the united states and canada.