A, most non metals are insulators
Answer:
ix chemical elements that comprise Group 2 of the periodic table
Explanation:
Calcium, Magnesium, Barium, Beryllium, Strontium, and Radium are alkaline earth metals.
Answer
• Improving the environmental performances
• Developing Green Mining technology
Explanation
The effect to the environment caused by opal mining are; impact on soils and geology, clearing of native vegetation disrupting flora and fauna, change in land use and effects of air quality.
Opal mining is currently examining environmental impacts and adopting measures that mitigate the impacts making the process less destructive to the environment.
With the current commitment to sustainability, opal companies are investing funds for Green Mining as a positive way to impact the environment before and after mining.
This is the part of where you can easily slip away
<span>The answer is: ultraviolet
The energy (E) of a photon is directly proportional to its frequency f, by Planck's
formula: E = hf, where h is Planck's constant (6.625 * 10**-34 joule-second).
The frequency is inversely proportional to the wavelength w by: f = c/w, where
c is the speed of light, 3.0 * 10**8 meters per second.
Combine these formulas and we see that the energy is inversely proportional to
the wavelength by: E = hc/w
If the energy is inversely proportional to the wavelength, a photon with twice the
energy has half the wavelength of our 442-nm. photon in this example.
So its wavelength is 221 nm. which is in the ultraviolet range.</span>
