Young Hagberd became apprehensive and unsure whether or not old Hagberd had recognised him, which is why he changed his tone from telling old Hagberd, "You've been identified," to "You've been identified." 'I've grown a beard like Father Christmas.' If elderly Hegberd did not recognise young Hagberd, the tone should be changed.

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?