When compared to stars near the middle of the diagram,how are stars in the upper right part of the Hertzsprung-Russell diagram different?

Question

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Stars in the upper right part of the Hertzsprung-Russell diagram (known as the red giants) are larger than stars near the middle of the diagram. They have exhausted the hydrogen fuel in their cores and have expanded to a larger radius as a result of the nuclear reactions in their outer layers. This expansion causes them to be classified as giant stars.

When Compared to Stars near the Middle of the Diagram,how