In a computer game, a builder can build a wall in ten hours while a destroyer can demolish such a wall completely in fourteen hours. Both, the builder and the destroyer were initially set to work together on level ground. But after 7 hours the destroyer was taken out. What was the total time (in hrs) taken to build the wall ?

Choose the corrct mirror image of the given figure.

Metals reacts with acids to give:

The 2016 Olympics was held in which city?

Consider the given question as true and decide which of the given statements is sufficient to answer the question.
Who among P, Q, R, S and T is lightest in weight?

Statements :
1. Q weight < P and S also S weight > T
2. R weight > Q but < T

Which of the following metals is stored in kerosene oil?

The focal length of a concave mirror with a radius of curvature of 20.0 cm is :

2/3 of a milk-water mixture was milk. There was 21 lit of the mixture. If 4 lit of water is added to it, the % of milk in the new mixture will be: