Which military invention, inspired by the automobile, was designed to protect soldiers during trench warfare?

I believe the answer is tanks.

Explanation:Tanks are armored vehicles designed to combine the military factors of fire, maneuver and protection. Although the concept of armored vehicles preceded the Great War, the tank was specifically developed to overcome the stalemate of trench warfare on the Western Front that followed the First Battle of Ypres (19 October-22 November 1914). The marrying of recent technological advances, such as the internal combustion engine with armor plating, enabled the tank’s development during World War I.

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.