I'm stumped on what seems to be a simple proof question, but I don't know what to do. Question: (c) Show that the LSE of the mean Y0 = B0 + B1x0 is a linear function of the data Yi, for i = 1,2,…,n where x0 is a known constant. Could someone help me to at least start this problem? So far I was thinking there'd be a way to substitute B0, but all I got is the estimate of B0 (B0 hat) and the estimate of B1 (B1 hat) found from previous parts of the question, but they don't seem applicable in this instance. Any ideas?