correct answer is : c) 176 meters, 22 m/sec

Explanation

Let the length of the train is KaTeX parse error: KaTeX doesn't work in quirks mode.
And the speed of the train is KaTeX parse error: KaTeX doesn't work in quirks mode.

In 1^st case,
When a train crosses a telegraph post then the distance covered by the train is the length (l) of the train.
Here, A telegraph post crosses by a train in 8 seconds.
KaTeX parse error: KaTeX doesn't work in quirks mode. Length of the train is: KaTeX parse error: KaTeX doesn't work in quirks mode. KaTeX parse error: KaTeX doesn't work in quirks mode. meter. _{(here distance is the train ‘l’)}
KaTeX parse error: KaTeX doesn't work in quirks mode. meter

In 2^nd case,
When a train crosses a bridge, it means the train covered its own length (l) and the bridge length, means sum of the train and bridge length.
Here, A bridge 264 meters long crosses by a train in 20 seconds.
KaTeX parse error: KaTeX doesn't work in quirks mode. Length of the train is:
KaTeX parse error: KaTeX doesn't work in quirks mode. _{[sum of the train and bridge length]} —–(i)
And distance covered by train is
KaTeX parse error: KaTeX doesn't work in quirks mode. _{[distance = speed × time]} —–(ii)

Here from (i) and (ii) we get,
KaTeX parse error: KaTeX doesn't work in quirks mode. _{[ Length of the train = distance covered by train]}
KaTeX parse error: KaTeX doesn't work in quirks mode. _{[put the value of ‘l’]}
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode.
KaTeX parse error: KaTeX doesn't work in quirks mode. The speed of the train is KaTeX parse error: KaTeX doesn't work in quirks mode.
And the length of the train is KaTeX parse error: KaTeX doesn't work in quirks mode. meter
KaTeX parse error: KaTeX doesn't work in quirks mode. meters
KaTeX parse error: KaTeX doesn't work in quirks mode. meters.
Ans: The length of the train is 176 meters, and the speed of the train is 22 m/sec.