Help me please please ;(

Slaves were a relatively inexpensive and plentiful labor force.

Explanation:

Slave owners had gotten away with being able to own slaves and not pay them, no matter how much work they had done. If they had gotten paid it was a very small amount, some were just paid a few cents a day.

2. a land bridge connected asia and north america thousands of years ago.

4. crossing the land bridge would have been simple for the first migrants.

5. people might have crossed a land bridge while hunting animals.

the answer is a. harriet tubman was a nurse on the battlefield.