Why were the 13th 14th and 15th amendments passed in this order

the 13th Amendment abolished the slavery, the 14th was effectively a bill of rights, guaranteeing the new black citizens their political and legal equality, the 15th stated in unambiguous terms that citizens' Rights had not to be limited by "race, color or previous condition of servitude".

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.

whose power in the senate is equal to the power of the speaker of the house?