(a) The bonus for the first year is $600. The basic salary is $30,000. To find the bonus as a percentage of the basic salary:

\(\text{Percentage} = \left( \frac{600}{30000} \right) \times 100 = 2\%\)

(b) The bonus at the end of the 24th year is calculated as follows:

\(Initial bonus = $600\)

\(Increase over 23 years = 23 \times $100 = $2300\)

\(Total bonus = $600 + $2300 = $2900\)

The basic salary at the end of the 24th year is:

\(\text{Salary} = 30000 \times 1.03^{23} \approx 59207.60\)

Express the bonus as a percentage of the salary:

\(\text{Percentage} = \left( \frac{2900}{59207.60} \right) \times 100 \approx 4.9\%\)