In a double story building clear height between floors is 3.3m and height of plinth is 0.6m above the foundation. thickness of the roof slab is 15cm and wall thickness is 20cm. if one of the walls of the buildings is continuous at the end and supported by cross wall at the other end and is of length 4m. find

1. Effective height of wall in first floor

2. Effective length of wall

3. Slenderness ratio