Estimating the Top of a Uniform

Level 8●●●○○ Medium~6 min

Problem

You observe X1,,XnX_1,\dots,X_n i.i.d. Uniform[0,θ][0,\theta] with θ\theta unknown. (a) What is the maximum-likelihood estimator of θ\theta? (b) Is it biased, and how would you correct it to be unbiased?