Question 21 MarkA mixture of cement, water, sand and gravel.AnswerConcreteView full question & answer→
Question 31 MarkA cement used for construction purpose.AnswerPortland cementView full question & answer→
Question 51 MarkAn element which helps prevent tooth decay which is used in toothpastes.AnswerFluorideView full question & answer→
Question 71 MarkA substance which is spread on a given surface and used for cleaning.AnswerSurfactantView full question & answer→