A magnifying glass is a combination of lenses of powers `+20 D and -5 D`. Calculate the magnifying power of the microscope, if the distance of distinct vision is 25 cm. Also, calculate the size of an object 3 cm high seen through the magnifying glass.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Calculate the Combined Power of the Lenses
The combined power \( P \) of the two lenses is given by the algebraic sum of their individual powers.

\[ P = P_1 + P_2 \]
...