i need help on A and B only.i have the rest figured out

We will proceed as follows:
a) The average rate of change between 1999 & 2002:
[tex]\frac{1483-1336}{2002-1999}=49[/tex]b) The average rate of change between 2001 and 2006:
[tex]\frac{745-1591}{2006-2001}=-169.2[/tex]