Answer:
1. 2/5
Explanation:
When it says the ratio is 5 to 2, that means 5 is always first:
5 : 2 is correct
5/2 is correct
10 : 4 is correct (multiplied 2 on both sides)
2/5 is incorrect because 2 is first. That means that this ratio would be 2 to 5, not 5 to 2.