# A portion of wastewater sample was subjected to standard BOD test (5 days, 200C), yielding a value of 180 mg/1. The reaction rate constant (to the base ‘e’) at 200 C was taken as 0.18 per day. The reaction rate constant at other temperature may be estimated by kr=k20 (1.047)T-20. The temperature at which the other portion of the sample should be tested, to exert the same BOD in 2.5 days, is

1.  4.90C

2.  24.90C

3.  31.70C

4.  35.0C

4

35.0C

Explanation :
No Explanation available for this question

# A prestressed concrete rectangular beam of size 300 mm x 900 mm is prestressed with an intial prestressing force of 700 kN at an eccentricity of 350 mm at midspan. Stress at top of the due to prestress alone, in N/mm2 is

1.  - 3.46 (tension)

2.  2.59 (compression)

3.  zero

4.  8.64 (compression)

4

- 3.46 (tension)

Explanation :
No Explanation available for this question

# Maximum size of a fillet weld for a plate of square edge is

1.  1.5 mm less than the thickness of the plate

2.  one half of the thickness of the plate

3.  thickness of the plate itself

4.  1.5 mm more than the thickness of the plate

4

1.5 mm less than the thickness of the plate

Explanation :
No Explanation available for this question

# Factor of safely adopted by IS : 800 - 1984 while arriving at the permissible stress in axial compression is

1.  2.00

2.  1.00

3.  1-67

4.  1.50

4

1-67

Explanation :
No Explanation available for this question

# For real values of x, cos (x) can be written in one of the forms of a convergent series given below

1.

2.

3.

4.

4

Explanation :
No Explanation available for this question

# Effective length of a rafter member between two nodes at a distance L, perpendicular to the plane of the truss is

1.  2.00 L

2.  0.85

3.  1.50

4.  1.00 L

4

0.85

Explanation :
No Explanation available for this question

# If the determinant of the  matrix  is 26,then the determinant of the matrix  is

1.  -26

2.  26

3.  0

4.  52

4

-26

Explanation :
No Explanation available for this question

# Allowable average shear stress in an unstiffened web for beams made of steel of grade 250 N/mm2 is

1.  250 N/mm2

2.  165 N/mm2

3.  150 N/mm2

4.  100 N/mm2

4

100 N/mm2

Explanation :
No Explanation available for this question

# A standard multiple-tube fermentation test was conducted on a sample of water from a surface stream. The results of the analysis for the confirmed test are given below. Sample size(ml) No.of positive results of 5 tubes No.of negative results of 5 tubes 1.0 4 1 0.1 3 2 0.01 1 4 MPN index and 95% confidence limits for combination of positive results when five used per dilutions(10 ml,1.0ml,0.1ml) Sample size(ml) combination of positives MPN index per 100 ml 95% confidence limit     Lower Upper 4-2-1 26 12 65 4-3-1 33 15 77 Using the above MPN Index table,the most probable number(MPN) of the sample is:

1.  26

2.  33

3.  260

4.  330

4

33

Explanation :
No Explanation available for this question

1.  0.20

2.  0.80

3.  1.00

4.  0.25

4