Skinner has suggested that it is best to focus on reinforcement and success rather than on punishing failure. Why is that

B.F Skinner was American psychologist.  He is considered to be the father of Operant conditioning. This theory uses positive and negative reinforcements to encourage wanted behavior whilst deterring unwanted and bad behavior.

Skinner suggested that if a behavior is followed by  reinforcement then that behavior is most likely to be repeated and if it is followed by punishment it wont be repeated.

it should be c, women were allowed to vote in all states because federal law supersedes state law.

"states can make their own laws, as long as they don't contradict what the federal law states. the states do not have the authority to pass a law that negates a federal law." -google

quote is the answer your looking for.