Final Answer:
The nominal rate of interest p.a. compounded semi-annually is approximately(d) 5.25%.
Step-by-step explanation:
To calculate the nominal rate of interest compounded semi-annually, we can use the compound interest formula:
![\[A = P \left(1 + (r)/(n)\right)^(nt)\]](https://img.qammunity.org/2024/formulas/business/high-school/qbt64n0zcusl0cr29qewk9ldkubuogsf2v.png)
Where:
is the future value of the investment

is the principal amount

is the nominal interest rate per compounding period (what we need to find),
is the number of times interest is compounded per year (2 for semi-annual),
is the time the money is invested for in years (78 months converted to years is

Rearranging the formula to solve for
, we get:
![\[r = n\left(\left((A)/(P)\right)^{(1)/(nt)} - 1\right)\]](https://img.qammunity.org/2024/formulas/business/high-school/c4lkmblsje1v916miwveuguyzyz640jnty.png)
Substituting the given values:
![\[r = 2\left(\left((7002.64)/(5000.00)\right)^{(1)/(2 * 78/12)} - 1\right)\]](https://img.qammunity.org/2024/formulas/business/high-school/pmjpu0u4utrdv3iptnrs43pgnf5r9rmgbt.png)
After performing the calculations, the nominal rate of interest (\(r\)) is approximately 0.0525, or 5.25%. Therefore, the correct answer is option (d) 5.25%. This indicates that, when compounded semi-annually, the investment grows from $5000.00 to $7002.64 over the 78-month period at an annual nominal interest rate of 5.25%.