
Actually Welcome to the Concept of the Optical Devices.
Now basically here the devices that can spread light over apart are the CONCAVE LENS and Convex mirror.
so the Answer is
C. B and D
Answer: Rn :)))) no explanation needed
Answer:
The intensity of sound (I) = 3.16 x 10⁻⁶ W/m²
Explanation:
We have expression for sound intensity level (SIL),

Here we need to find the intensity of sound (I).

Substituting
L = 67 dB and I₀ = 10⁻¹² W/m² in the equation

The intensity of sound (I) = 3.16 x 10⁻⁶ W/m²