A company is offering early retirement for some of their employees. There are multiple tiers of employees based on their years at the company.

Tier 1: at least 17 years

Tier 2: at least 13 years

Tier 3: 10-13 years

The years worked for the employees have a normal distribution with a mean of years worked of 9 years and the standard deviation of 4 years.

What percentage of employees for each of the first three tiers are eligible for early retirement?

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