initial capital = $800
interest = 6%
time = 4 years
the entire amount after 4 years:
[tex]100\%+6\%=106\%=1.06\\\\\$800\cdot(1.06)^4\approx\$800\cdot1.2625\approx\$1009.98[/tex]
The interest: $1009.98 - $800 = $209.98
[tex]Answer:\boxed{the\ interest=\$209.98}[/tex]