Write an explicit formula for an, the nth
term of the sequence 6, 12, 18,

The answer is a: the eggs have half as many chromosomes as the body cells

Ihaven't done that yet, so no idea,but this is not the right place to ask

All of them are man made

the glands which are associated with each description is given below:

pancreas - is an endocrine and exocrine gland that secretes juices with enzymes for digestion. salivary glands- with protection and digestion in the mouth. liver- secretes bile for digestion.   lachrymal glands - secrete tears to moisten eyes and protect them from particles and infection.   sweat gland -regulates water, salt, and temperature. oil glands - to form a protective barrier on the skin.   goblet cells - secrete mucus for protection.