SSE and b1 are independent? How can I prove that?

#1
at simple linear regression,
are b1 and SSE independent.
but how can i prove that? :confused:

my text book said
'SSE is independent of each of the estimators Hat_beta_0(b0) and Hat_beta_1(b1).'

should i get covariance(SSE, b1) ? how?:confused: