L = illuminance
A = surface
i = intensity
L = i / A ==: i = L * A
i = 6 lux * 4 m^2 = 24 lumen
Answer:
Natural science is concerned with the description, prediction, and understanding of natural phenomena based on empirical evidence from observation and experimentation. It can be divided into two main branches: life science (or biological science) and physical science.
Explanation:
V: velocity of wave
f: frequency
L: wavelenght
v = fL => L = v/f => L = (3x10^8)/(900x10^3) => L = 3.33 x 10^2m