Answer:
4.96 × 10⁵ Pa
Explanation:
F = mg

This force is evenly distributed on the three leg
radius, r = d/2
= 2.8 / 2
= 1.4 cm = 0.014 m
total cross sectional area of the three legs, A = 3*pi*r^2

Pressure due to weight,
P = Weight/A

P = 4.96 × 10⁵ Pa
Answer: The wave can flip upside down.
Reflection is the bending of a wave when it cannot pass through. For example, plain mirrors which are flat, a ray of light hits the mirror and is reflected from the mirror since it cannot pass through
When reflection occurs the speed and frequency of the wave does not change but the wave is flipped upside down.
The speed does not change because speed is affected by the change in medium the frequency also remains the same since the energy of the wave does not change.
It depends. If you are driving and the person doesn't look like a serial killer, you should stop.
I believe the answer is B, a real and inverted image is formed on the side of the lens opposite the rubber ducky. The focal length is 15 cm and therefore the center of curvature (2F) will be 30 cm. When the object is placed between F and 2F (in this case 20 cm) in front of a convex lens, an inverted, real image is formed on the other side of the lens.