Answer
$6
Work Step by Step
We can calculate simple interest on a loan by using the formula $I=prt$ (where I is the interest, p is the principal, r is the rate of interest, and t is the amount of time - expressed in years).
$t=\frac{1}{2}$, because 6 months equals one half of a year
$I=prt$
$I=400\times.03\times\frac{1}{2}=6$ dollars
