Answer:
The 99% confidence interval is
Step-by-step explanation:
From the question we are told that
The sample size is n = 100
The sample mean is 
The population standard deviation is
From the question we are told the confidence level is 99% , hence the level of significance is
=>
Generally from the normal distribution table the critical value of
is
Generally the margin of error is mathematically represented as

=>
Generally 95% confidence interval is mathematically represented as
=>
=>
FUTURE VALUE = PRESENT VALUE * (1 + r)^t
PV = 220,000
r = 3%
t = 7 years
FV = 220,000 * (1 + 3%)^7
FV = 220,000 * (1.03)^7
FV = 220,000 * 1.22987386542487
FV = 270,572.25
C, I was in class this morning and we say the formula for this is $6000 x 1.15 to the power of 5. That is $12068.14
Hope I could help :)