Answer
$0$, see explanations.
Work Step by Step
Step 1. Use the Limit Laws, we have:
$$\lim_{v\to c^-}L=\lim_{v\to c^-}L_0\sqrt {1-\frac{v^2}{c^2}}=L_0\sqrt {1-\frac{\lim_{v\to c^-}v^2}{c^2}}=L_0\sqrt {1-\frac{c^2}{c^2}}=0$$
Step 2. This result means that when the speed of the object approaches the speed of light, its length to the observer will be close to zero.
Step 3. A left-hand limit is necessary because the speed of light is the maximum speed achievable by any object.
