Why does cotton wrinkle when it gets wet or sweaty why is formaldehyde unpleasant?

ответ на первый вопрос: If you sweat, spend time in a humid area, spill a liquid on yourself or wash your shirt, it wrinkles. It does this because the hydrogen links in the cotton react to water, causing the fabric to bend out of shape and form wrinkles in the cloth.

ответ на второй вопрос: At low levels, breathing in formaldehyde can cause eye, nose and throat irritation. At higher levels, formaldehyde exposure can cause skin rashes, shortness of breath, wheezing and changes in lung function.