What qualifies as a dependent (a) 25 year old son/daughter making$5k per year living at home, (b) 21 year old friend going to school and living in your home (c) 65 year old mother living with her son/daughter (d) 12 year old stepdaughter living in mexico

None of the exposed cases qualify as dependent. Qualify those direct relatives such as children, stepchildren, grandchildren, brothers or nephews under 19 years old, or under 24 if they are studying full time, and must prove that they live with the person from whom they are dependent for more than 6 months. Parents over 65 years old do not qualify as dependents, unless they have special needs or have never worked, just the fact of living with a child does not make them dependent.

answer: when the substance contain the two parts (polar and non-polar) like soap.

explanation:

soap is produced from the basic hydrolysis of ester "saponification", it is considered as a salt of hydrocarbons. the soap molecule contains the two parts: a polar group   (-coo-na+) and a non-polar group (r-hydrocarbon part). the polar group is called the head and the tail is the non-polar group. the polar group is hydrophilic in nature (water loving) and the non-polar group is hydrophobic in nature (water repelling).the polar/non-polar nature of a substance is useful that it can dissolve the non-polar substances by the polar part and also can dissolve the polar substances by the non-polar part. it commonly used in detergents and soaps.

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