教えてくだされ。
今、Javaの入門書を2冊読んでます。
　(1)Leran to program with Java
　(2)Java2 a beginner's guide
の2冊ですが、floatとdoubleの値が違います。

　(1)Leran to program with Java
では、
>I explained that variables declared as Float data types require 32 bits or 4 bytes of computer memory to hold them.
>Values for the Float data type can range from -3.4 x 10^38 to 3.4 x 1038.
>I explained that variables declared as Double data types require 64 bits or 8 bytes of computer memory.
>Values for the Double can range from -1.8 x 10^308 to 1.8 x 10^308

と書いてあります。
　(2)Java2 a beginner's guide
では、
>The type float is 32 bits wide and has a range of 1.7e-308 to 1.7e+308.
>The double type is 64 bits wide and has a range of 3.4e-38 to 3.4e+38.

となってます。