PLEASE HELP The cost of an iPhone has a decay rate of one-fourth every 6 months. The iPhone initially costs $735.

The equation that represents this is
y = ( blank )( blank )^x

how much money is the iPhone worth after 2 years? $

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?

Aweekly newspaper charges $72 for each inch in length and one column width. what is the cost of an ad that runs 2 column inches long and 2 columns wide? its not 288

The equation represents the function f, and the graph represents the function g. f(x)=3(5/2)^x determine the relationship between the growth factors of f and g. a. the growth factor of g is twice the growth factor of f. b. the growth factor of f is twice the growth factor of g. c. the growth factor of f is 2.5 times the growth factor of g. d. the growth factor of f is the same as the growth factor of g.