The formula used to calculate the total amount at the end of the period is given to be:
![A=P(1+(r)/(n))^(nt)](https://img.qammunity.org/2023/formulas/mathematics/high-school/39foo2gerf9tf1ffk32zwshrn339mz02kv.png)
where
A = Accrued amount (principal + interest)
P = Principal amount
r = Annual nominal interest rate as a decimal
t = time in decimal years.
From the question, we have the following parameters:
![\begin{gathered} P=3000 \\ r=1.25\%=0.0125 \\ t=4 \\ n=2\text{ \lparen compounded semi-annually\rparen} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/62ma06q13ay77yeljz5zqnv0b857c6799m.png)
Therefore, we can solve the final amount as follows:
![\begin{gathered} A=3000(1+(0.0125)/(2))^(2\cdot4)=3000(1.00625)^8 \\ \therefore \\ A=3153.32 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/5eyfqf5i9ut04dcm99e2oo9f7bvi52b3tz.png)
The interest will be calculated to be:
![\begin{gathered} I=A-P \\ I=3153.32-3000=153.32 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/hsrwalnutafmyb3fqpk7www198tiuzdx1g.png)
Therefore, the final amount is $3,153.32.
The interest is $153.32.