TASK DEFINITION: In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
PROBLEM: Question: A person is digging up rocks, and wants to get the oldest ones. The person will dig 
 Answer: deeper

SOLUTION: Older rocks are at the bottom and younger rocks are at the top.

PROBLEM: Question: Mike is watching how particles of reactants function, and sees that they are very far apart. Considering that the concentration of them is very low, the chance of them colliding together is 
 Answer: low

SOLUTION: At higher concentrations, particles of reactants are crowded closer together, so they are more likely to collide and react.

PROBLEM: Question: A person with light skin can absorb how much vitamin D? 
 Answer: a lot

SOLUTION:
Pigments in the skin act like a filter that can prevent the skin from making vitamin D. As a result, people with darker skin need more time in the sun than people with lighter skin to make the same amount of vitamin D.