Set 1: Linear Inequalities (Advanced)

Choice A is correct. Choice A is the correct answer. The alarm sounds when the temperature is OUTSIDE the safe range. 1. Safe Range: $34\leq t \leq 40$ (inclusive) 2. Unsafe (Alarm): strictly less than 34 OR strictly greater than 40 3. Inequality: $t < 34$ or $t > 40$ Strategic Tip: The negation of "between inclusive" is "outside exclusive". Choice B is incorrect because it represents the SAFE range. Choice C is incorrect because it includes the boundary values 34 and 40 as unsafe, but the problem says "inclusive" is safe. Choice D is incorrect because it represents a strictly safe range, excluding boundaries.