When Tao Ying rides the bus alone, she usually does not pay for the ticket because she believes that her paying or not paying does not affect the bus's routine; however, she acts in accordance with the situation, paying for the ticket when the conductor appears responsible but not when he appears casual and careless.

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?