Robin Clark Has a Cell Phone That She Uses Only

question 251

Short Answer

Robin Clark has a cell phone that she uses only for emergencies. The cost of the phone is $40 a month. The cellular company is offering unlimited nights and weekends for an additional $10 a month ($120 a year). Robin thinks it would be "cool" to have this benefit and, after all, $10 a month is not much. Show Robin how much she will have in 20 years if she invests this $120 a year at 9% instead of accepting the unlimited nights and weekends offer.

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Definitions:

Avogadro's Number

The number of units in one mole of any substance (defined as its molecular weight in grams), approximately 6.022 x 10^23 units.

Mass

A measure of the amount of matter that an object contains, often expressed in kilograms or grams.

Mole

A unit in chemistry used to express amounts of a chemical substance, defined as containing exactly 6.02214076×10²³ particles, such as atoms or molecules.

S Atoms

Sulfur atoms, which are nonmetallic elements with the atomic number 16 known for their yellow crystals and role in biological systems.