A projectile has a range of `40 m` and reaches a maximum height of `10 m`. Find the angle at which the projectile is fired.

Explanation

To find the angle at which the projectile is fired, we can use the relationships between the range, maximum height, and the angle of projection. Here is a step-by-step solution:

### Step 1: Write down the equations for range and maximum height
The range \( R \) of a projectile is given by the formula:
\[ R = \frac{u^2 \sin(2\theta)}{g} \]
where \( u \) is the initial velocity, \( \theta \) is the angle of projection, and \( g \) is the acceleration due to gravity.
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