phrase: three billion liiters "is"?

[Sweetpumpkin]

Hello,

Here's a voa news again:

[Alan]

Hi SP,

'Is' is used here because 'three billion liters' is regarded as a quantity/an amount and then it would be singular.

Alan
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[Sweetpumpkin]

Then, Alan, is it possible to say "Three billion liters are..." here? I think so and it is more proper for English grammar.

sweetpumpkin

[Sweetpumpkin]

I googled and checked a corpus. I found lots of examples using "liters is" "kilograms is" "meters is". I cannot explain it, but the "three billion liters" is kind of... a large amount of ethanol or something... I can understand. :)