List one way in which congress can check the power of the president

The president exercises a check over Congress through his power to veto bills, but Congress may override any veto (excluding the so-called "pocket veto") by a two-thirds majority in each house. When the two houses of Congress cannot agree on a date for adjournment, the president may settle the dispute.

The president exercises a check over Congress through his power to veto bills, but on the other hand Congress may override any veto  by a two-thirds majority in each house, this means that they can discard the veto and never go through with it. When the two houses of Congress cannot agree on a date for adjournment, the president may cancel the dispute.

the answer is: must pay taxes on profits

since it is considered as a part of your income, profits from investments is eligible for tax payment.

the tax from your investment could be influenced by how long you decided to sell it. united states promotes keeping your investment for long term period. so, the tax rate for investments that you sell in less than one year is typically higher compared to investments that you sell in more than one year period.