Zina makes deposits of $1200 at the end of each six month period. A 2-year period implies 4 deposits. The first one doesn't earn interest. 3% per annum is changed to 1.5% per half-year to be consistent with the fact that she is making deposits at the end of each six month period.
...though why anyone would open an account and leave it empty for 6 months before making the first deposit is known only to Zina, or whatever question writer dreamed up this scenario...
Zina makes deposits of $1200 at the end of each six month period. A 2-year period implies 4 deposits. The first one doesn't earn interest. 3% per annum is changed to 1.5% per half-year to be consistent with the fact that she is making deposits at the end of each six month period.