Hi seoulapp,
1) If your performance is such that your accelerate to V1 and stop distance is 2/3 rds of the the runway length available (so you can show you will be below 60 kts by the last 1/3 rd) - then you can ignore the stop end RVR. So you can take off under 500 150 100
2) Mid point RVR is below limits - so you can't take off.
3) You can only assess the take off visibility for the first part. The mid point is beyond 500m so you can't judge the visibility there - you have to accept the RVR value - so you can't take off.
ATC don't know your limits - so provided the RVR is equal to or above the minimum RVR published for the airport, they can offer clearance.