Bro thanks for the links but my internet connection is very very slow recently and not working properly. I tried to download the BARC file atleast ten times but could not succeed.
not sure about it. Russia denied the technology but India produce it in India. There may be some kind of agreement or DRDO developed some critical systems for the engine.
About 900 km altitude, it needs lots of discussion. You are right about the speed, it will be much higher like ICBM which will make it difficult to intercept. But apart from that there are other indications that such high altitude mean Agni-4 has much greater range. We will talk about this in details later.
abe chod be uss machar ko ,mein RCMJ ki baat kar raha ,salle ko bahut khujli ho rahee hey ,USSE aisa ungli karunga ,salla zindigi bhar mujhe yaad rakhega .