Spot the mistakes in the given statements and correct them.
a) Hypothyroidism is due to excess secretion of thyroxine.
b) Hyperthyroidismi is due to less secretion of thyroxine.

Explanation

### Step-by-Step Solution:

1. **Identify the First Statement**: The first statement is "Hypothyroidism is due to excess secretion of thyroxine."

- **Mistake**: This statement is incorrect because hypothyroidism is actually caused by a deficiency of thyroxine, not an excess.
- **Correction**: The correct statement should be "Hypothyroidism is due to less secretion of thyroxine."

2. **Identify the Second Statement**: The second statement is "Hyperthyroidism is due to less secretion of thyroxine."
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