Refer to exercise $5.$a$.$ Use a $=\mathrm{.}01$ to test the hypotheses$225$H: B$,=$ B$2=0$Ha: B$,$ and$/$or B$,$ is not equal to zerofor the model y $=$ Bo $+$ B$,$x$,+$ B$,$x$2+$ e$,$ where$*,=$ television advertising $($$$1000$s$)$X$2=$ newspaper advertising $($$$1000$s$)$Use a $=\mathrm{.}05$ to test the significance of B$,.$ Should x$,$ be dropped from the model?Use a $=05$ to test the significance of B$,.$ Should x$,$ be dropped from the model?