Answer:
[tex]\begin{gathered} a)\text{ }A=25,335.40 \\ b)\text{ }A=25,409.78 \\ c)\text{ }A=25,424.48 \\ d)\text{ }A=25,379.71 \end{gathered}[/tex]Step-by-step explanation:
Compound interest is represented by the following expression:
[tex]\begin{gathered} A=P(1+\frac{r}{n})^{nt} \\ \text{where,} \\ A=\text{ amount} \\ P=\text{ Principal} \\ r=\text{ Interest rate decimal form} \\ n=\text{ number of times interest is compounded per unit t} \\ t=\text{time} \end{gathered}[/tex]Then,
a) Compounded semiannually:
If semi-annually, then n=2.
[tex]\begin{gathered} A=20,000(1+\frac{0.06}{2})^{2\cdot4} \\ A=20,000(1.03)^8 \\ A=25,335.40 \end{gathered}[/tex]b) Compounded monthly:
If monthly, then n=12
[tex]\begin{gathered} A=20,000(1+\frac{0.06}{12})^{12\cdot4} \\ A=20,000(1.005)^{48} \\ A=25,409.78 \end{gathered}[/tex]c) Compounded continuously:
If continuously (daily), then n=365
[tex]\begin{gathered} A=20,000(1+\frac{0.06}{365})^{365\cdot4} \\ A=25,424.48 \end{gathered}[/tex]d) Compounded quarterly:
If quarterly, then n=4.
[tex]\begin{gathered} A=20,000(1+\frac{0.06}{4})^{4\cdot4} \\ A=25,379.71 \end{gathered}[/tex]