Answer:
He must invest R297 521 today.
Step-by-step explanation:
The compound interest formula is given by:

Where A(t) is the amount of money after t years, P is the principal(the initial sum of money), r is the interest rate(as a decimal value), n is the number of times that interest is compounded per year and t is the time in years for which the money is invested or borrowed.
Banabas must pay his ex-wife an amount of R350 000 in two years’ time.
This means that 
Interest rate of 8.15% per annum compounded monthly:
This means that
.
Amount he must invest today:
This is P. So




He must invest R297 521 today.
Null hypothesis: 
Alternative hypothesis: 
The null is based on a recent study that 81% of the population (in this case senior citizens) takes at least one medication. The alternative hypothesis is basically the flip of the claim made in the null.
If Amelia wanted to know if the percentage was less than 81%, then the alternative would be p < 0.81
If Amelia wanted to know if the percentage was larger than 81%, then the alternative would be p > 0.81
However, she wants to know if the percentage is 81%.
Answer:
A
Step-by-step explanation: