<u>Answer:
</u>
The build-up of three oxygen created our ozone layer around two billion years ago.
<u>Explanation:
</u>
- The ozone layer is a part of the stratosphere which is located right after the troposphere in the atmosphere of the Earth.
- The ozone gas is made up of the abundance of three oxygen molecules combining with the ultraviolet radiation emitted by the Sun.
- The development of the ozone layer happened around two billion years ago when the oxygen concentration levels on the planet began to rise slowly and gradually.
Answer:
D)
Explanation:
Legend is over the map, thus, making the map harder to read.
<u>Answer</u>:
When Uranium-238 decays, it emits 8 Alpha particles and 6 beta particles before finally becoming the stable daughter product. The atomic number and mass number of the daughter product is 92 and 234 respectively.
<u>Explanation</u>:
In the process of decay of Uranium-238, it emits alpha particles, and the resultant product is Thorium-234, which turns into Protactinium-234, and this Protactinium-234 undergoes the beta decay to form the Uranium-234.
As per the question, a stable daughter product is created after the emission of alpha and beta particles, this implies that Uranium-234 is a stable product after the decay of Uranium-238. Therefore, the atomic number is 92 (number of protons) and the mass number is 234 (protons+neutrons) which is also the element of the naming.
<span>cool winters, warm summers, ample rainfall</span>
Answer:
Compared to the valley, the ridge is relatively wet and cool.
Explanation:
The ridge is relatively wet and cool in comparison with the valley. Due to the mountains that surround the valley, the cool air does not enter the valley. This makes the valley hotter in contrast with the ridge. Also, it makes the ridge wet owing to the pressure and the low temperature that the air has.