Statement-1: `2-3%` Gypsum by weight is mixed with cement
Statement-II: Gypsum increases the rate of setting of cement

Four numbers are chosen at random (without replacement) from the set {1, 2, 3, ....., 20}. Statement-1: The probability that the chosen numbers when arranged in some order will form an AP Is 1/(85) . Statement-2: If the four chosen numbers form an AP, then the set of all possible values of common difference is {1, 2, 3, 4, 5}. (1) Statement-1 is true, Statement-2 is true; Statement-2 is not the correct explanation for Statement-1 (2) Statement-1 is true, Statement-2 is false (3) Statement-1 is false, Statement-2 is true (4) Statement-1 is true, Statement-2 is true; Statement-2 is the correct explanation for Statement-1

Cement is one of the most important building material of the present time. It is a dirty greyish heavy powder containing calcium aluminates and silicates. The important raw materials neede for the manufacture of cement are limestone, clay and gypsum. the main step in the manufacture of cement is the heating of raw meal or slurru in the rotary kiln at a very high temperature 1400-1600^(@)C . Finally 2% or 3% gypsum is added. When cement is mixed with water and left as such for sometime, it becomes a hard mass. This is known as setting of cement. It is believed that varous aluminates and silicates present in the cement form hydrates with water which seperate in the form of gel. the gel formed start losing water partly by evaporation and partly by forming hydrates with unhydrated constituents. this results in the formation of a hard mass. Setting of cement is

Cement is one of the most important building material of the present time. It is a dirty greyish heavy powder containing calcium aluminates and silicates. The important raw materials neede for the manufacture of cement are limestone, clay and gypsum. the main step in the manufacture of cement is the heating of raw meal or slurru in the rotary kiln at a very high temperature 1400-1600^(@)C . Finally 2% or 3% gypsum is added. When cement is mixed with water and left as such for sometime, it becomes a hard mass. This is known as setting of cement. It is believed that varous aluminates and silicates present in the cement form hydrates with water which seperate in the form of gel. the gel formed start losing water partly by evaporation and partly by forming hydrates with unhydrated constituents. this results in the formation of a hard mass. Gypsum is added to portland cement

Cement is one of the most important building material of the present time. It is a dirty greyish heavy powder containing calcium aluminates and silicates. The important raw materials neede for the manufacture of cement are limestone, clay and gypsum. the main step in the manufacture of cement is the heating of raw meal or slurru in the rotary kiln at a very high temperature 1400-1600^(@)C . Finally 2% or 3% gypsum is added. When cement is mixed with water and left as such for sometime, it becomes a hard mass. This is known as setting of cement. It is believed that varous aluminates and silicates present in the cement form hydrates with water which seperate in the form of gel. the gel formed start losing water partly by evaporation and partly by forming hydrates with unhydrated constituents. this results in the formation of a hard mass. Portland cement does not contain

Cement is one of the most important building material of the present time. It is a dirty greyish heavy powder containing calcium aluminates and silicates. The important raw materials neede for the manufacture of cement are limestone, clay and gypsum. the main step in the manufacture of cement is the heating of raw meal or slurru in the rotary kiln at a very high temperature 1400-1600^(@)C . Finally 2% or 3% gypsum is added. When cement is mixed with water and left as such for sometime, it becomes a hard mass. This is known as setting of cement. It is believed that varous aluminates and silicates present in the cement form hydrates with water which seperate in the form of gel. the gel formed start losing water partly by evaporation and partly by forming hydrates with unhydrated constituents. this results in the formation of a hard mass. Concrete is a mixture of

Statement-1 : In the molecule will form intramolecular H-bonding to a greater extent . Statement-2 : Bond order greater than three is not possible . Statement-3 : Increase in percentage of P orbital increases the directional nature of bond .

Statement 1 is True: Statement 2 is True; Statement 2 is a correct explanation for statement 1 Statement 1 is true, Statement 2 is true;2 Statement 2 not a correct explanation for statement 1. Statement 1 is true, statement 2 is false Statement 1 is false, statement 2 is true Statement I: cos^3alpha+cos^3(alpha+(2pi)/3)+(alpha+(4pi)/3)=2cosalphacos(alpha+(2pi)/3)cos(alpha+(4pi)/3) because Statement II: In a+b+c=0=>a^3+b^3+c^3=3a c a. A b. \ B c. \ C d. D

Statement I: Two particle are moving towards each other due to mutual gravitational attraction. The momentum of each particle will increase. Statement II: The rate of change of momentum depends upon F_(e xt) .

Statement -1 Solubility of alcohols decreases with increasing molecular weight Statement -2 : Increases in hydrophobic group decreases proportion of hydrogen bonding .

Statement-1: Expected major product from the above reaction Statement-2:With increase in electrophilicity on gt C=O group, rate of attack of nuecleophile increases.