Is it safe to reuse plastic bottles for water?

Question by Generic Person: Is it safe to reuse plastic bottles for water?

I know about plastic containing carcinogens, but I recall hearing that it only applied for things under high or low temperatures. Is it safe to keep a bottle around to refill with water when I get thirsty? It is going to be left out on my desk, so no refrigeration or heat to really worry about.

Best answer:

Answer by SuperVibrationalEscrow
As safe as re-using a plastic cup. It is good to wash them out with hot water and dish soap from time to time just to prevent bacteria.

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Q&A: What do the numbers mean on plastic recycle-ables?

Question by Merit Servus: What do the numbers mean on plastic recycle-ables?

what is the difference between all the numbers and why do some take them and some don’t?

Best answer:

Answer by oikos
The numbers tell the type of plastic used, from 1 (PETE) to 7 (Other). The ones easiest to recycle are numbers 1 & 2 (HDPE). The others (3-7) can be used for plastic lumber but there are few facilities that manufacture it.

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Q&A: A manufacturer of plastic bags is ready to make a recall.?

Question by : A manufacturer of plastic bags is ready to make a recall.?

A manufacturer of plastic bags is ready to issue a recall of their product if more than 3.8% of them are defective. They examine 478 of their bags, and of those 478 bags, 12 of them are found to be defective.

What is the test statistic z-value of this study?
Please please please help me i have no idea how to do this!

Best answer:

Answer by Aaron
Well, your sample proportion, p-hat, is 12/478 = .0251.
The z-score for this would be calculated with z = (p-hat – hypothesized p)/(stdev)
The stdev for the sampling distribution of sample proportions is ?((p-hat*q-hat)/n), where q-hat = 1 – p-hat.
So, z = (.0251 – .038)/?((.0251)(.9749)/478) = -1.80

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