How to add the vector symbol on a letter?

Ho to add the vector symbol on a letter like this: $ \vec{r}$ ?

Consider the following code:

k0 = Graphics[{Text[      Style["\!\(\*SubscriptBox[\(K\), \(0\)]\)", 12], {0.5, -0.05}],      Thick, Arrow[{{0, 0}, {1, 0}}]}]; k1 = Graphics[{Text[      Style["\!\(\*SubscriptBox[\(K\), \(0\)]\)-q", 12], {0.5, 0.2}],      Thick, Arrow[{{0, 0}, {0.8, 0.2}}]}]; q = Graphics[{Text[Style["q", 12], {0.9, 0.15}], Thick,      Arrow[{{0.8, 0.2}, {1, 0}}]}]; l = Graphics[{Text[Style["\[Theta]", 12], {0.2, 0.03}], Thick,      Line[{{0, 0}, {0.2, 0}}]}]; Show[k0, k1, q, l, Boxed -> False]