who we can extract network id and host id from dotted decimal?

Question

if we have 14.98.12.8?
199.234.45.78
246.246.245.223

which class and which id network and which host id?

Answer 1

Without subnet masks, you can't be sure.

By the book, they would be class A,C and D.

http://www.freesoft.org/CIE/Topics/26.htm

Answer 2

Assuming default subnet masks

14/ 98.12.8
199.234/ 45.78

The last one used to be class E, it's reserved now.
You need to take the left nibble of 246 for the network id and the rest would be the host address.