Answer:  You should deposit about $17014 or little more 
Step-by-step explanation: 
use the compound interest formula. 
 A= p( 1 + r/n)^nt
Where A is the amount you will save over some years . 
p is the principal or start up amount mostly known as the initial fee. 
r is the interest rate represent by a decimal so 7% will be 0.07. 
n is the number of times the interest is being applied annually. Semiannually means twice. So n will be 2. 
T is the time the money will elapsed. So in 5 years the money will elapse. Now input the values into the formula and solve for p the principal. 
 24,000 = p( 1 + 0.07/2)^2*5 
24,000= p( 1 + 0.035)^10 
24000 = p( 1.035)^10 
24000 = p( 1.41059876062) Divide both sides by 1.41059876062 
 p = 17104 
Which means you should deposit about $17014 or little more