The annual interest is 2000 * 8/100 = $<<2000*8/100=160>>160.
Interest for two and a half years is 160 * 2.5 = $<<160*2.5=400>>400.
So, Adam's father will have 2000 + 400 = $<<2000+400=2400>>2400 after 2 and a half years.
#### 2400