which statements correctly describe the prope...
which statements correctly describe the properties of air? select three options. air has mass but no weight. air pressure is created by the weight of the atmosphere pushing on earth’s surface. pressure is a measure of how tightly molecules are packed. denser air is heavier than less dense air. air is less dense at higher altitudes.
Answer
# Answer:
- B. Air pressure is created by the weight of the atmosphere pushing on Earth’s surface.
- D. Denser air is heavier than less dense air.
- E. Air is less dense at higher altitudes.
# Explanation:
## Step1: Analyze option A
Mass is a measure of the amount of matter, and weight is the force exerted on a mass by gravity. Air has mass and thus has weight due to Earth's gravity, so option A is incorrect.
## Step2: Analyze option B
Air pressure is indeed the result of the weight of the air - the atmosphere - pushing down on Earth's surface. This is correct.
## Step3: Analyze option C
Pressure is force per unit area. Density is a measure of how tightly molecules are packed. So this option mis - defines pressure, and is incorrect.
## Step4: Analyze option D
Density is mass per unit volume. Denser air has more mass per unit volume, so it is heavier than less dense air. This is correct.
## Step5: Analyze option E
At higher altitudes, there is less air above pushing down, so air molecules are more spread out and air is less dense. This is correct.