170) For masonry work with solid bricks, consistency of mortar should be

171) Water retentivity for brick masonry should not be less than

172) Minimum compressive strength in N/mm2 for H1 type mortar used for masonry is

173) Rich cement mortars are more liable to cracking as compared to lean mortars because rich mortars have

174) Cement mortars richer than 1 : 3 are not used in masonry because (i) there is no gain in strength of masonry (ii) there is high shrinkage (iii) they are prone to segregation Of these statements