A glass window is to be fit in an aluminum frame. The temperature on the working day is `40^@C` and the glass window measures exactly ` 20 cm xx 30 cm.` What should be the size of the aluminum frame so that there is no stress on the glass in winter even if the temperature drops to `0^@C`? Coefficients of linear expansion for glass and aluminum are `9.0 xx 10^(-6)C^(-1)` and ` 24xx10^(-6)C^(-1)` respectively.

Explanation

To find the size of the aluminum frame that will fit the glass window without causing stress during temperature changes, we need to calculate the dimensions of the aluminum frame at the working temperature (40°C) based on the dimensions of the glass window (20 cm x 30 cm) and the coefficients of linear expansion for both materials.

### Step-by-Step Solution:

1. **Identify Given Data:**
- Dimensions of the glass window:
- Length (L) = 20 cm
- Width (W) = 30 cm
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