Write structure of the products of the following reactions: 
(a) Anisole (methoxybenzene) reacts with HI.
HI protonates the ether oxygen and breaks the C–O bond.
The methyl group leaves as methyl iodide (CH$_3$I) and phenol (C$_6$H$_5$OH) is formed.
So, products are: Phenol + CH$_3$I.
(b) Phenol activates the benzene ring strongly towards electrophilic substitution.
With concentrated nitric acid, multiple nitro groups attach to ortho and para positions.
So, 2,4,6-trinitrophenol (picric acid) is formed.
This reaction is an example of nitration of an activated aromatic compound.
(c)The Grignard reagent (Cyclohexyl–MgBr) attacks the carbonyl carbon of formaldehyde.
This forms an alkoxide intermediate.
On acid hydrolysis, the alkoxide is protonated to give a primary alcohol.
So, the product is cyclohexylmethanol (Cyclohexane–CH$_2$–OH).
(i) Explain Aldol condensation with example.
(ii) How are the following conversions achieved:
(a) Benzene Benzaldehyde, (b) Ethanoic acid ethanol.
A racing track is built around an elliptical ground whose equation is given by \[ 9x^2 + 16y^2 = 144 \] The width of the track is \(3\) m as shown. Based on the given information answer the following: 
(i) Express \(y\) as a function of \(x\) from the given equation of ellipse.
(ii) Integrate the function obtained in (i) with respect to \(x\).
(iii)(a) Find the area of the region enclosed within the elliptical ground excluding the track using integration.
OR
(iii)(b) Write the coordinates of the points \(P\) and \(Q\) where the outer edge of the track cuts \(x\)-axis and \(y\)-axis in first quadrant and find the area of triangle formed by points \(P,O,Q\).