Let {x1, ...;In} be iid exponential with parameter A. The pdf is (a) Write the likelihood and the loglikelihood, and find the sufficient statistic. (b) The following data are high-stress failure times (in hours) of spherical vessels used in a high pressure environment on the space shuttle. 50.1, 70.1, 137.0, 166.9, 170.5, 152.8, 80.5, 123.5, 112.6, 148.5, 160.0, 125.4 Assuming an exponential model, estimate the parameter A by the method of moments