Answer:
I think it is difficult to determine what has caused climate change in the distant past because it must have been a long time ago so geologists can't carry out different experiments and figure out what gases the planet had conjured, so geologists can only make predictions based off the evidence they currently have from what the planet looked like before. The planet must have changed over the years, therefore the climate has also changed in the future, so they cannot work with how the planet looked in the past.
<u>First Symbol </u>: Cobalt (Co)
Its Group Number - 9
Its Period Number - 4
Its Family Name - Transition Metal
<u>Second Symbol</u> : Silicon (Si)
Its Group Number - 14
Its Period Number - 2
Its Family Name - Semiconductor
<u>Third Symbol</u> : Astatine (At)
Its Group Number - 17
Its Period Number - 6
Its Family Name - Halogen
<u>Fourth Symbol </u>: Magnesium (Mg)
Its Group Number - 2
Its Period Number - 3
Its Family Name - Alkaline Earth Metal
<u>Fifth Symbol</u> : Xenon (Xe)
Its Group Number - 18
Its Period Number - 5
Its Family Name - Noble Gas
the awnser to ur question is D
c. energy and object has.....
All you would do is for a, 10 times 2 is 20 so it would be 20-dB
For b, 10 times 4 is 40 so it would be 40-dB
<span>For c, 10 times 8 is 80 so it would be 80-dB</span>
