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Hello, this is 6 Minute English from BBC Learning English. I'm Rob.

And I'm Georgina.

Oh, it's freezing cold outside today, Georgina.

Make sure you wrap up warm.

I'll put my woolly hat on.

When I was growing up, I was told that you lose half your body heat from your head.

No, don't believe that, Georgina.

It's just a popular myth.

You know, something people think is true, which actually isn't.

Like, bulls get angry when they see the colour red or goldfish only have a three-second memory.

Oh, I thought red really did make bulls angry.

But you're right, there is some disagreement over the age or question.

Should I wear a hat when it's cold outside?

In this programme, we'll be asking how much body heat we lose from our head

and discovering that a simple answer isn't so easy to find.

But first, it's time for my quiz question.

And let's start by asking someone who knows all about surviving in the cold,

the US Army.

According to the Cold Weather Survival chapter of the US Army Field Guide,

how much heat is lost in the cold through an uncovered head?

...