1).   Two simply supported beams B₁ and B₂ have spans l and 2l respectively. Beam B₁ has a cross-section of 1 x 1 units and beam B₂ has a cross-section of 2 x 2 units. These beams are subjected to concentrated loads W each at the centre of their spans. The ratio of the maximum flexural stress in these beams is

• 4    
• 2    
• 1/2    
• 1/4