The heights of school desks have a normal distribution with mean 69 cm and standard deviation \(\sigma\) cm. It is known that 15.5% of these desks have a height greater than 70 cm.

(i) Find the value of \(\sigma\).

When Jodu sits at a desk, his knees are at a height of 58 cm above the floor. A desk is comfortable for Jodu if his knees are at least 9 cm below the top of the desk. Jodu's school has 300 desks.

(ii) Calculate an estimate of the number of these desks that are comfortable for Jodu.