**971. Generally acceptable nominal size of aggregates for reinforced concrete, is**

A. 10 mm

B. 15 mm**C. 20 mm**

D. 25 mm

**972. For heavily reinforced concrete member, the nominal maximum size of the aggregates should be restricted tomain bars**

A. 5 ram less than the minimum clear distance between the**B. 5 mm less than the minimum cover to the reinforcement**

C. smaller of (a) and (b)

D. greater of (a) and (b).

**973. The average 28 days compressive strength of at least three 15 cm concrete cubes prepared with available water as compared to the average strength of three similer concrete cubes prepared with distilled water, should be at least**

A.70%

B.80%**C.90%**

D. 95%.

**974. The pH value of water to be used in concrete shall generally be**

A. not more than 7

B. not less than 6**C. not less than 5**

D. not more than 6.

**975. All reinforcement should be free from**

A. loose mill scales

B. loose rust

C. paints**D. all the above.**

**976. For all practical purposes, the modulus of elasticity of steel is assumed****A. 200 If.N/mm2**

B. 225 kNimm2

C. 250 IfN/mm2

D. 275 kN/mm2.

**977. M 30 grade concrete means, its compressive strength of 15-cm cube, is 30 N/mm2 after**

A. 3 days

B. 7 days

C. 21 days**D. 28 days.**

**978. A body is said to be in equilibrium if**

A. it moves horizontally

B. it moves vertically**C. it rotates about its C.G.**

D. none of these.

**979. If EH and IV are the algebraic sums of the forces resolved horizontally and vertically respectively, and EM is the algebraic sum of the moments of forces dbout any point, for the equilibrium of the body acted upon**

A. EH = 0

B. EV = 0

C. Elll = 0**D. all the above.**

**980. The forces acting normally on the cross section of a bar shown in Fig. 21.1 introduce****A. compressive stress**

B. tensile stress

C. shear stress

D. none of these.

**NOTEIF YOU THINK ANY OF THE MCQ ABOVE IS WRONG.PLEASE COMMENT WITH CORRECT ANSWER AND ITS DETAIL EXPLANATION IN COMMENT BOX.THANK YOU**