Shear-it, Inc., produces paper shredders. Shear-it is considering a new shredder design for home offices. The marketing vice president believes that a basic unit in a variety of attractive colors could be sold for $70. Shear-it requires that all new products yield 30% profit.
What is the target cost of the new shredder?

a) $21 b) $100 c) $91 d) $49 e) $63.70

PAIRS OF SUBSTITUTES

tea - coffee  

butter - margarine

petroleum - natural gas

PAIRS OF COMPLEMENTARY GOODS

printer - ink cartridge

pen-refill

Explanation:

Substitutes are goods that can replace other goods.   On the other hand, complementary goods go hand in hand with one another.  This implies that while substitutes can be used in isolation, complementary goods cannot be used in isolation of each other.  For example, if one needs a pen, they also require a refill.