Electromagnetic spectrum facts — wavelengths and the visible window Pick the correct combined statement about gamma-ray wavelengths, radio-wave wavelengths, and the visible band extent used in remote sensing.

Introduction / Context:
Remote sensing spans a wide portion of the electromagnetic spectrum (EMR). Understanding approximate wavelength scales helps relate sensor bands (visible, NIR, SWIR, TIR, microwave) to physical interactions including absorption, scattering, and emission.

Given Data / Assumptions:

• Order-of-magnitude wavelength values are acceptable.
• “Visible” refers to human-vision band ~0.4–0.7 μm.
• Long-wavelength radio can reach kilometre scales.

Concept / Approach:
Gamma rays sit at the extreme short-wavelength end (on the order of 10^-12 to 10^-10 m). Radio waves span millimetres to kilometres; very long waves approach 10^6 m. The visible band is a narrow window between ultraviolet and near-infrared, about 0.4–0.7 μm.

Step-by-Step Reasoning:

Verification / Alternative check:
Textbook EMR charts show the visible as a tiny slice, framed by UV below 0.4 μm and NIR above 0.7 μm; radio spans many orders of magnitude.

Why Other Options Are Wrong:

• Each single statement is correct; selecting only one omits the others.
• None of these: incorrect because all given statements hold.

Common Pitfalls:
Confusing micrometres (μm) with millimetres (mm); mixing “typical value” with “only value” — spectrum bands cover ranges.

Final Answer:
All of these