1) To determine which is the function from the table we need to attentively look for a constant factor in the y-column.
2) As we can see from this table, the factor we can tell that goes from 64 to 16 and then 4 is 1/4. Or in decimal form 0.25. So, we can tell the factor "b" is going to be 1/4 considering this model:
3) Let's pick one point (0,4) and plug it to find the other elements:
And finally, we can tell the function is: