It's kinda hard to explain but I found a reliable website
http://www.history.com/topics/mcculloch-v-maryland
According to a British army doctor, a cotton plantation should have one slave per two acres, coffee should have two slaves per three acres, and sugar plantations (the worst of the worst) should have one slave per acre
Answer: A dicovered electricity and it’s use as weapon
Explanation: I got the answer from quizizz