Explanation:
the last option is the correct answer
A double helix is <span>a pair of parallel helices intertwined about a common axis, especially that in the structure of the DNA molecule. or in other words a double spiral.</span>
Phenomena such as star explosions, neutron stars, black holes etc. are studied with the help of extremely powerful and sensitive telescopes.
These sophisticated instruments are able to see more than our own eyes can. Thus, they detect wavelengths outside of those found in our visible spectrum, such as X-rays etc.
The most sophisticated telescopes are those that are placed in space such as the Hubble or Spitzer Space Telescope. In this way, these instruments are able to circumvent the Earth's atmosphere that may block the view of the sky. Thus, in space, they have the optimal conditions to observe and study in detail such phenomena.
Why Earth's inner core<span> has speed trap for </span>seismic waves<span>. </span>Earth<span> has multiple layers: the crust, the mantle, the liquid </span>outer core<span> and the </span>solid inner core<span>. Something is not quite right inside the </span>Earth's core<span>. When </span>seismic waves<span> from earthquakes ripple through its </span>solid<span> center, they hit a speed bump.</span>
