Could anyone please grade my SAT essay?

This was the prompt: Is conscience a more powerful motivator than money,fame or power?

This was my essay:

Conscience is able to bring out our most human side even if it means risking our own welfare. People often think that thirst for power, fame or wealth is what drives human beings on a daily basis, but nothing is as compelling for people than conscience and ethics.

When people feel strongly about a cause, they will fight to protect it even if it gets in the way of wealth. Shark Tank once featured a group of young men who sold shirts that promoted environmental awareness and for every shirt sold, they would plant a tree. One of the investors offered them more than the money needed to start their business, but he’d only do this if they produced cheaper shirts in China. Because they felt it was unethical to produce their shirts were employees were paid less, they refused the offer even though it was tempting for their business.

Another example of the power of conscience is Mario Benedetti, an Uruguayan poet who lived during Uruguay’s dictatorship. He was born into a wealthy family who held a powerful position in the country. Because he knew how corrupt and inequitable the government was, he refused to use his socio-economic position to his advantage. Instead, he used it to protest against the regime and demand justice. His conscience was stronger than his desire for wealth or power.

Once, I was at a restaurant and after paying, the cashier gave me more money than what I had paid. Even though I was short on money at the moment, and she was oblivious of the fact that she had given me more money, I returned it and told her. It felt wrong to take it, even if I needed it.

It is evident that ethics and conscience do in fact have more power over humans than selfish desires. It is in our most basic nature to be ethical and conscientious. It is necessary for a society to be driven by justice and awareness in order for it to thrive.