the life time (in days) of an electronic device has the pdf f(x;theta) = (1/theta) * e ^ (-x/theta) for x>=0.

find the numerical value of theta (with a hat on it), the MLE the parameter theta, based on the random sample.

2, 3, 2.5, 2.5, 2, 3, 2.4, 2.6, 2, 3

is theta(hat) is an unbiased estimator of theta?

find the MLE estimator for the squaeroot of (theta + 2).