What evidence do the authors include to support the central idea that the sugar plantations' cheap labor source changed from enslaved people to indentured Indians? The sugar plantations depended on cheap labor.
The sugar plantations had a 24-hour cycle.
Gladstone asked the shipping company to provide workers.
Gladstone exhibited the chained body of Quamina.
i need help

Gladstone asked the shipping company to provide workers.

Explanation:

The authors explain in the provided passage the way things went after the final end of slavery. They state how plantations depended on cheap labor and enslavement before, but that slaves were replaced by Indian people who were workers.

That idea can fully be seen in the sentence part “Gladstone asked it [a shipping company] to provide a hundred workers [...] from India”. It sums up how Gladstone asked for workers, instead of for slaves, for it, which refers to the previously mentioned shipping company. The passage then explains how many workers came with each ship to work for Gladstone.

i'm pretty sure you can use the word uproar