Answer:
Year - (1993 - 1995)
Step-by-step explanation:
Rate of change in the number of toys sold = 
In the interval (1990 - 1993),
Rate of change in number of toys sold = 
= 
= 4000
In the interval (1993 - 1995),
Rate of change = 
= 
= 5000
In the interval (2000 - 1995),
Rate of change = 
= 
= 3000
In the interval (2006 - 2000),
Rate of change = 
= 
= 1000
Therefore, rate of change in the number of toys sold is greatest in the interval (1993 - 1995).