Answer:
Candles
Explanation:
The answer is the first option or "candles." In ancient times the people would lit candles and place them in difference places in their homes, temples, etc... to produce light. It's not option B because light emitting diodes are used to light up toys and such which weren't invented in ancient times. It's not option C because fluorescent bulbs are long light bulbs used to light up huge spaces without as many light bulbs which were again not invented at the time, and it's also not option D because incandescent bulbs are you usual light bulbs which weren't invented at the time.
Hope this helps.
If you go to a website known as 'Wolfram' and type in the question they should be able to answer it. It's basically a very smart calculator. I'd add a link but I don't want to seem like I'm advertising, and it's against Brainly rules.
Answer:
The process of evaporative cooling helps the body is explained below in complete details.
Explanation:
Your body performs the application of the evaporative process when secreting. Sweat, which contains 90 percent water, commences evaporating. ... This appears in a cooling impression (described as evaporative cooling) that serves to sustain body temperature and cools the body down when it becomes too hot.
Answer: 
Explanation:
The confidence interval for population mean is given by :-
Given : Sample size : 
Sample mean : 
Standard deviation : 
Significance level : 
Critical value : 
Now, the 95% confidence interval estimate of the (true, unknown) mean sound intensity of all food processors of this type :-
