Answer:
The claim is rejected
Step-by-step explanation:
Claim: UCF is advertising their bachelor in Economics with the statistic that the starting salary of a graduate with a bachelor in economics is $ 48,500 according to Payscale (2013-13).
Null hypothesis: 
Alternate hypothesis :
n = 50
Since n is more than 30 .
So we will use Z test
x=43350
Standard deviation = 15000

Refer the z table
p value = 0.00776

p value < 
So, We are failed to accept null hypothesis
Hence The claim is rejected
Hey! The surface area is 294. Have a great day. :-)
Step-by-step answer:
Given:
Initial monthly salary = $5000
New salary = 10% less
Salary a year after = 15% more
Solution:
New salary
= 5000 * (100-10)%
= 5000 * 90%
= 5000 * 90/100
= 4500
Salary a year after
= 4500 * (100+15%)
= 4500 * 115%
= 4500 * 115/100
= 45*115
= 5175