The lac operon includes the following genes and their products:
'i' gene: Produces the repressor protein (iii).
'z' gene: Produces $\beta$-galactosidase (i), which breaks down lactose.
'a' gene: Produces transacetylase (iv).
'y' gene: Produces lac permease (ii), which facilitates lactose entry into the cell.

A ladder of fixed length \( h \) is to be placed along the wall such that it is free to move along the height of the wall.
Based upon the above information, answer the following questions:
(iii) (b) If the foot of the ladder, whose length is 5 m, is being pulled towards the wall such that the rate of decrease of distance \( y \) is \( 2 \, \text{m/s} \), then at what rate is the height on the wall \( x \) increasing when the foot of the ladder is 3 m away from the wall?