Shear Strength of Reinforced Concrete Beam

1.As per IS:456, the value of shear strength of concrete (τ) is a function of -
2.In a four pointing loading setup, which type of loading is middle part of the beam subjected to ?
3.What type of cracks are observed in the beam portion subjected to shear force in the four-point loading test ?
4.Two rectangular reinforced concrete sections X and Y are similar in all aspects except the longitudinal tension reinforcement in section Y is 10% more. Which one of the following statements is correct ?