The option C) y = 15/x
a) y = 15 x is an example of direct variation, with proportionality constant = 15
b) is an example of linear variation (it is the equation of a straight line that does not pass through the origin)
c) y = 15/x => y*x = 15 = constant which is the characteristic of an inverse relation
d) y = x/15 is an example of an inverse relation, with proportion constant = 1/15
Answer:

Step-by-step explanation:
Density is the ratio of an object's mass to its volume, and it measures how compact an object is. The density of an object, p, is directly proportional to its mass, m, and inversely proportional to its volume, V:


This cannot be simplified any further.
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