これはもちろんdouble Aと読みます。意味は単三電池です。0:56 double A aize.
http://www.youtube.com/watch?v=jic-tAgHqRE 0:19 rechargeable AA batteries
http://www.youtube.com/watch?v=AUNHdoGWXWM 1:24 the battery case slides out and takes 2 triple As. 注; triple A = AAA = 単四電池
https://www.youtube.com/watch?v=sywGKW9FBnY 0:59 quadruple-A battery (AAAA battery) 単5
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https://www.youtube.com/watch?v=4-uIC-K0vFs 3:14 a quadruple-A battery
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1;53 it lasts about a year on a simple quad A battery. このペンは単5電池で約一年もつ。
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