The sticky substances in cigarettes that coat the lining of the lungs are

Tar

Explanation:

tar is a sticky substance consisting of inorganic and organic compounds.

Tar is very toxic and can cause cancer when deposited on the lungs

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2