In handling air-entraining admixtures the beneficial amount of entrained air depends upon certain factors like
1. Type and quantity of air-entraining agent
2. Water-cement ratio of the mix
3. Strength of aggregates
4. The extent of compaction of concrete
1. 1, 2 and only
2. 1, 2 and 4 only
3. 1, 3 and 4 only
4. 1, 2, 3 and 4