Given an n$-$element ordered array, we apply the Binary Search on this array. Let B$\_$w be the worst$-$case efficiency, and B$\_$a be the average$-$case efficiency. Which of the following formulas is correct? a$)1+2$B$\_$wB$\_$a $<$ B$\_$w$^2+$ B$\_$a$^2$ b$)1+2$B$\_$wB$\_$a $=$ B$\_$w$^2+$ B$\_$a$^2$ c$)1+2$B$\_$wB$\_$a $>$ B$\_$w$^2+$ B$\_$a$^2($a$)($b$)($c$)$