If C is creep coefficient, f is original pre-stress in concrete, m is modular ratio, E is Young's modulus of steel and e is shrinkage strain, the combined effect of creep and shrinkage is:

A. A circular curve B. A straight line C. A parabolic curve D. An elliptical curve

A. Equal or less than 5 kg/cm², no shear reinforcement is provided B. Greater than 4 kg/cm², but less than 20 kg/cm², shear reinforcement is provided C. Greater than 20 kg/cm², the size of the section is changed D. All the above

A. Low strength concrete only B. High strength concrete only C. Low strength concrete but high tensile steel D. High strength concrete and high tensile steel

A. $${\frac{1}{4}^{{\text{th}}}}$$ of the span B. $${\frac{1}{5}^{{\text{th}}}}$$ of the span C. $${\frac{1}{6}^{{\text{th}}}}$$ of the span D. $${\frac{1}{7}^{{\text{th}}}}$$ of the span