Inverse Trigonometric Function Model

The function $h$, defined by $h(t) = 4.217 \tan^{-1} (0.7t - 0.026)$, models the number of people, in thousands, who have entered a museum $t$ hours after it opens, for $0 \leq t \leq 8$. According to the model, at what time $t$ does the 4000th person enter the museum?