Sound is heard clearly in summer than in winter Why ?

Sometimes , a crackling sound is heard while taking off a sweater during winters. Explain.

[A] : Some plants flower only in summers & some only in winters. [R]: Such plants require specific photoperiods tor flowering.

A car sounding its horn at 480 Hz moves towards a high wall at a speed of 20 ms^-1 . If the speed of sound is 340 ms^-1 , the frequency of the reflected sound heard by the passenger sitting in the car will be nearest to

Discuss why wearing more layers of clothing during winter* keeps us warmer than wearing just one thick piece of clothing.