I. The explanations are as follows:
2. Here, the main verb is 'looked'. Therefore, 'linking' is the present participle form of the verb 'link' and is not used in continuous tense. The two actions indicated are 'linking arms' and 'looked doubtful.'
3. The main verb is 'said'. Therefore, 'staring' is the present participle form of the verb 'stare' and is not used in continuous tense. The two actions indicated are 'said' and 'staring'.
4. The main verb is 'became'. Therefore, 'knowing' is the present participle form of the verb 'know' and is not used in continuous tense. The two actions indicated are 'knowing' and 'became melancholy.'
5. In this sentence, the main verb is 'turned'. Therefore, 'leaving' and 'standing' are the present participle form of the verb 'leave' and 'stand' respectively, that are not used in continuous tense.
II. Examples of similar sentences are as follows:
1. He was kneeling on the floor in the next room tinkering with a part of his motorcycle over some newspaper spread on the carpet.
2. She watched along the canal, seeing him come out of the shadows, imagining her own consequent excitement.
3. Jansie frowned, sensing she was covering.
4. I feel the pangs of doubt stirring inside me.
5. But all the same, it makes me despondent, this knowing I'll never be able to show them they're wrong to doubt me.
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 \(P,O,Q\).