Primary radar can determine altitude.
What rubbish! No it can't - that's what Secondary radar (SSR) is there for.
The only primary radar that can detect altitide are purpose built height finders (conventional radars put on their sides) which can give the height on one aircraft (normally) by scanning up and down. They have to be rotated manually in Azimuth to physically point at the aircraft to achieve that.
The only other one is a phased array head such as the Military's PAR (Precision Approach Radar) which again will scan in a limited area only on the final approach.