Which of these individuals would be subject to the "kiddie tax"?

Dana, age $12,$ earned $$800$ in dividends, with no other income.

Gia, age $15,$ worked as a lifeguard all summer and earned $$2,800$ with no other income.

Kyle, age $14,$ earned $$1,000$ in interest and had a $$1,800$ royalty from a family oil well. He had no other income.

Paul, age $19,$ is taking a year off before starting college. He received $$4,200$ in dividends with no other income.