A. is a duty of congress. They can say a law is unconstitutional based in their views on the law but they cant declare one unconstitutional. But the President can declare a law unconstitutional and change it.
The completion of the Transcontinental Railroad greatly affected companies that made products in that it made it far easier for them to transport their goods over long distances to markets, which greatly increased profits and output.
These are concurrent powers
They could get mad or confused it really depends on what the concerns are about the children
