Su-30MKK questions

Firstly is the second and third version designated Su-30MKK2/Su-30MKK3 or SU-30MK2/Su-30MK3 or Su-30MKK-2/SU-30MKK-3 or Su-30MK-2/SU-30MK-3.

What radar do the three versions have?

Do Chinese Flankers use any form of underwing fuel tanks, ISTR the original Su-27SMK proposal mentioned 2000 litre drop tanks?