Question: how to mix concrete for a slab
Option 0: A concrete mix of 1 part cement : 2 parts sand : 4 parts coarse aggregate should be used for a concrete slab. Ad water to proper consistency. Concrete must be placed after half an hour of mixing.
Option 1: A concrete mix of 1 part cement : 2 parts sand : 4 parts coarse aggregate should be used for a concrete slab. Ad water to proper consistency. Concrete must be placed within half an hour of mixing.
Answer: 1