Solution
[tex]\begin{gathered} 1)\text{ Answer, This is GROWTH } \\ 2)\text{ The initial amount of people wo own a cell phone is },\text{ means when t = 0} \\ P(t)=20(1.075)^t \\ p(t)\text{ = }20(1.075)^0 \\ p(t)\text{ = 20 }\times\text{ 1} \\ p(t)\text{ = 20} \end{gathered}[/tex][tex]\begin{gathered} 3)\text{ To }\det er\min e\text{ the growth/decay rate, we have} \\ p(t)=20(1.075)^t \\ p(t)=20(1+0.75)^t \\ \text{Answer, growth rate is: 0.75 =0.75\%} \\ \end{gathered}[/tex]