Answer:
0.41 (correct to 2 decimal place)
Step-by-step explanation:
If 
Let
, then 
We want to determine the rate of increase
after one day
and 


Rate of increase after one day, i.e. t=1
= 0.407 =0.41 (correct to 2 decimal place)
Answer:
Z-score is 1.75
Step-by-step explanation:

You can find the Z-score from the standard normal table. Just read the table in reverse.
In this case, Z = 1.75
Add your two totals together,
1860 + 5775 = 7635, next we multiply our answer by 1.082,
$8261.07 is the total cost.