A concave mirror has a radius of curvature of 56 cm.

Step 1. The points. $f = \dfrac{56\ \text{cm}}{2} = 28\ \text{cm}$. So $F$ is $28\ \text{cm}$ and $C$ is $56\ \text{cm}$ from the pole.

Step 2. (a) The object is at $C$. The image is at $C$ too: real, inverted and the same size.

Step 3. (b) The object is between $C$ and $F$. The image is beyond $C$: real, inverted and larger. The formula agrees: $\dfrac{1}{v} = -\dfrac{1}{28\ \text{cm}} + \dfrac{1}{40\ \text{cm}} = -\dfrac{3}{280\ \text{cm}}$, so $v = -93.3\ \text{cm}$.