Need to see if these are correct

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

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

Dexter read 11 science fiction books and 5 history books. lena read 9 science fiction books and 4 history books. compare the students’ ratios of science fiction books to history books. 1. determine the ratios’ form:    science fiction books to history books 2. write the ratios as fractions:    dexter: 115; lena: 94 3. rewrite with a common denominator. 4. compare. 5. answer the question. determine which shows the correct comparison of the ratios for this problem.