instruction:
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.
question:
Question: Mike needed to get a dark picture . In order to get the darkest photo, Mike made the exposure 
 Answer: shorter
answer:
The longer the exposure, the more light that the telescope can gather to make the image.


question:
Question: Tasha is studying birth rates in various countries. She looks at two countries. In South Africa, the food supply is currently higher than in Australia. Because of this, the birth rate in South Africa, compared to Australia, will be 
 Answer: higher
answer:
Low food supply or a lack of space can lower birth rates, increase death rates, or lead to emigration.


question:
Question: Tom was digging in his backyard one day, after two inches he picked up an oval shaped rock. Tom kept digging and after twelve inches he picked up a square shaped rock, which rock was younger? 
 Answer: The Oval Shaped Rock
answer:

The upper rock layers are much younger.