List I | List II | ||
|---|---|---|---|
| A | Mesozoic Era | I | Lower invertebrates |
| B | Proterozoic Era | II | Fish & Amphibia |
| C | Cenozoic Era | III | Birds & Reptiles |
| D | Paleozoic Era | IV | Mammals |

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?