#15: The number of layers of the Earth varies according to different classifications. However, the most common one is the so-called "chemical", which distinguishes among Crust, Mantle and Core (check it here https://phys.org/news/2015-12-earth-layers.html). True, the mantle can be divided in two layers, but the same applies to the core. Hence the question has several possible answers, and as such is wrong (especially because it lacks an explanation).
Unfortunately, this test will not be able to receive a prize:
Missing explanations. All explanations simply repeat the correct answer. E.g. #q30, #q1, etc.
#9: The word "earth" originates from Proto-Germanic *ertho: Proto-Germanic (https://en.wikipedia.org/wiki/Proto-Germanic_language) is absolutely NOT the same thing of "German". Check the etymology of "earth" here: https://www.etymonline.com/word/earth#etymonline_v_941
#15: The number of layers of the Earth varies according to different classifications. However, the most common one is the so-called "chemical", which distinguishes among Crust, Mantle and Core (check it here https://phys.org/news/2015-12-earth-layers.html). True, the mantle can be divided in two layers, but the same applies to the core. Hence the question has several possible answers, and as such is wrong (especially because it lacks an explanation).
#26: Asking for "the oldest language in the world" doesn't make any sense. What do you mean? The oldest written language? The oldest language still in use? As for the oldest written account, Egyptian would be the correct answer (https://en.wikipedia.org/wiki/List_of_languages_by_first_written_accounts); and as for the oldest language still in use, Tamil may be one of them, but the topic is very controversial as there is no real evidence for it (https://www.forbes.com/sites/quora/2018/03/26/what-is-the-oldest-language-ever-discovered/).
#27: It's the Moon that orbits the Earth, not the opposite. Do we still need an evidence for this? :D
Also, explanations in this quiz do not explain anything, but just repeat the correct answer...