The blank can be filled by several different options. Here are some of them.
1) Congress has the power to declare war- The US cannot go to war until both the House of Representatives and Senate vote on it.
2) Congress has the power to pass laws.
3) Congress has the power to levy taxes. - This ensures that the government programs are receiving proper financing.
4) Congress has the power to pay debts created by the federal government.
4)
