Answer:
Manuela should put $23,985.24 into an 18 month CD.
Explanation:
Manuela wants to have $26,000 in 18 months CD that earns simple interest of 5.6% a year calculated semiannually.
Since it is simple interest so in 18 months (1.5 years) it will earn = 5.6 × 1.5 = 8.4%.
Formula for Simple interest
A = P( 1 + rt)
A = amount ( 26,000 )
P = Principal ( we have to find out )
r = Rate of interest in decimal 8.4% ( 0.084 )
t = time ( 1 )
Let the principal amount be x
Now we put the values in formula to find the value of x.
26,000 = x ( 1 + 0.084 × 1 )
26,000 = x ( 1.084 )
x =

x = 23,985.23985 rounded to 23,985.24
Manuela should put $23,985.24 into an 18 month CD.