To find the angle of elevation formed by the ramp, we can use the inverse sine function. The sine of the angle can be expressed as the ratio of the opposite side (the height difference between the two levels) to the hypotenuse (the ramp length).
Let:
- \( h = 2.5 \) feet (the height difference)
- \( L = 4 \) feet (the length of the ramp)
The sine of the angle \( \theta \) can be calculated using the formula:
\[ \sin(\theta) = \frac{\text{opposite}}{\text{hypotenuse}} = \frac{h}{L} \]
Substituting the values:
\[ \sin(\theta) = \frac{2.5}{4} \]
Now calculating the value:
\[ \sin(\theta) = 0.625 \]
Next, we will use the inverse sine function to find the angle:
\[ \theta = \sin^{-1}(0.625) \]
Using a calculator:
\[ \theta \approx 38.68^\circ \]
Rounding to the nearest whole degree gives us:
\[ \theta \approx 39^\circ \]
Therefore, the approximate angle of elevation formed by the ramp is 39°.