I need help really bad! I have literally no clue what the answer is to this question

In which source of water would a wave travel the fastest? o ice o cold o room temperature o hot mark this and return save and exit next

Yuto and hila attempted to solve the same inequality. their work is shown below. which statement is true about the work shown above? yuto is correct because he isolated the variable correctly and reversed the inequality symbol. yuto is incorrect because he should not have reversed the inequality symbol. hila is correct because she isolated the variable correctly and reversed the inequality symbol. hila is incorrect because she should not have reversed the inequality symbol.

Acertain volume of water contains 100000 hydrogen atoms and 50,000 oxygen atoms how many hydrogen atoms are in a volume of water containing 4 million oxygen atoms