1. **Problem 39:** Compute $40 - \frac{1}{40}$. We need to subtract a fraction from a whole number. 2. **Formula and rules:** To subtract a fraction from a whole number, express the whole number as a fraction with the same denominator. 3. **Intermediate work:** Express 40 as $\frac{40 \times 40}{40} = \frac{1600}{40}$. Now subtract: $$\frac{1600}{40} - \frac{1}{40} = \frac{1600 - 1}{40} = \frac{1599}{40}.$$ 4. **Answer for Question 39:** The result is $\frac{1599}{40}$, which corresponds to option d. 5. **Problem 40:** Round 36 to two decimal places. 6. **Explanation:** The number 36 is an integer and can be written as 36.00 to two decimal places. 7. **Answer for Question 40:** Rounded to two decimal places, 36 is 36.00, which corresponds to option d.