What was the most negative change that occurred in the 1920?why

Which one of these best describes an interest group

The congress shall have power to lay and collect taxes, duties, imposts and excises, to pay the debts and provide for the common defence and general welfare of the united states . .; to borrow money on the credit of the united states; to regulate commerce with foreign nations, and among the several states, and with the indian tribes. —constitution of the united states, article i, section 8 which of these are expressed powers granted by this part of article i, section 8? check all that apply. lay and collect taxes and duties pay debts regulate american indian groups regulate commerce within states borrow money regulate commerce with foreign nations

What was the most important consequence of the large-scale ecological changes in africa two hundred thousand years ago?