Please help I'm so confused

Methylphenidate is used to treat ADHD (attention deficit hyperactivity disorder). A patient is prescribed two 10.1 mg Methylphenidate tablets each day. Methylphenidate patches release Methylphenidate into the body by absorption through the skin. The patches come with different amounts of Methylphenidate. The maximum amount of Methylphenidate in one brand of patch supplies a patient with 20. mg of Methylphenidate per day.

Determine the amount of Methylphenidate a patient may take using 2 tablets (in mg) Be sure your answer has the correct number of significant figures.

They work by increasing activity in the brain, particularly in areas that help control attention and behaviour. Methylphenidate is used to treat children with attention deficit hyperactivity disorder (ADHD). It helps with hyperactivity and impulsive behaviour, and allows them to concentrate better.

Explanation:

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