X-rays . are blocked by the ionosphere
are less dangerous than ultraviolet rays
have very long wavelengths
are not emitted by the sun

have very long wavelengths

Explanation:

The first  X-ray image was captured by Wilhelm Conrad Roentgen (1895), who accidentally discovered these rays while experimenting with vacuum tubes. X-rays are high-energy electromagnetic radiation with very long wavelengths (in the range of 0.01 to 10 nanometers, nm). They are shorter in wavelength than ultraviolet rays and longer than gamma rays. X-rays have energies ranging from 100 electron-volts (eVs) to 100 kiloelectron-volts (keVs). On the other hand, the radio waves are blocked by the planet's ionosphere and, therefore, they cannot reach the Earth.

a community that experiences major changes undergoes progress

picture a world where computers are building made-to-order personalized robotic arms and synthetic organs, drones are circulating above mars! due to the rapid growth of technology, the future has never been more unpredictable, and it presents a huge challenge in education: we are teaching students how to work in a future that we have never been unsure of. it is widely predicted that in eight years’ time, there will be more jobs in the fields of science, mathematics, technology and engineering than in any other discipline. and, as the technology continues to develop, it will soon become clear that addressing social problems will involve more innovative thinking, and analytical and technical knowledge than ever before. undeniably, there are no subjects that encourage innovative and creative thinking, deep thought, problem solving and independence more than the stem subjects. while it is widely commented on that there is a need to reimagine the ways stem subjects are taught in schools by embracing a more interactive and innovative approach to appeal to more students, it should come as no surprise that some of the most reputable educational organizations in the world are already implementing changes to embrace stem. harvard, for example, announced in 2014 that they were increasing their computer science faculty by over 50% and has since introduced computer science as a core subject for all freshmen. the urgency of supporting stem subjects at a young age is becoming more relevant than ever, as adopting a keen interest in the curricula needs to happen early. however, beyond the age issue is one of gender.

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