## 21. If the ratio of center to center spacing of intersecting walls to actual thickness of intersecting wall is more than 20, then the stiffening coefficient for wall proper will be

## 22. Where a structural component or a system is providing lateral support to five or more walls or columns, the lateral load to be resisted may be taken as __________ of the total vertical load on the most heavily loaded wall or column in the group.

## 23. If the horizontal cross-sectional area of a wall is 1200 cm^{2}, then the basic stress shall be multiplied by a reduction factor equal to

^{2}, then the basic stress shall be multiplied by a reduction factor equal to

## 24. If ‘H’ is the height of wall between centers of supports, then the effective height of wall where concrete floors have a bearing on wall irrespective of the direction of span will be

## 25. 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

(i) There is no gain in strength of masonry

(ii) There is high shrinkage

(iii) They are prone to segregation