Sol invests $10,000 at age 20. Sol wants the investment to be worth $45,000 by age 38. If interest is compounded continuously, what rate of return does Sol need to reach that goal? Enter your answer as a decimal rounded to the thousandths place.

A3cm×3cm\greend{3\,\text{cm} \times 3\,\text{cm}} 3cm×3cm start color greend, 3, space, c, m, times, 3, space, c, m, end color greend rectangle sits inside a circle with radius of 4cm\blued{4\,\text{cm}} 4cm start color blued, 4, space, c, m, end color blued . what is the area of the shaded region? round your final answer to the nearest hundredth.