In the figure shown, a large multimode fiber with $n_{\text{core}}=1.5$ and $n_{\text{clad}}=1.2$ is used for sensing. A portion with the cladding removed passes through a liquid with refractive index $n_{\text{liquid}}$. An $\text{LED}$ is used to illuminate the fiber from one end and a paper is placed on the other end, $\text{1 cm}$ from the end of the fiber. The paper shows a spot with radius $\text{1 cm}$. The refractive index $n_{\text{liquid}}$ of the liquid (rounded off to two decimal places) is ______________.
