SAT math practice question: Exponential functions

 
Try the following SAT math practice question (Calculator Permitted) that tests your understanding of percent changes in exponential functions.

Question(Calculator Permitted):

The exponential function $h$ decreases by $36\%$ for each increase by $2$ in the value of $x$. Which of the following could define $h$ ?

1. $\quad h(x)=3(0.36)^x$
2. $\quad h(x)=2(0.64)^x$
3. $\quad h(x)=3(0.8)^x$
4. $\quad h(x)=2(1.36)^x$