For the following questions answer them individually
An article when sold at a gain of 5% yields Rs.15 more than when sold at a loss of 5%. Find its cost price.
In Mendeleev’s periodic table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later?
A train crosses a pole in 20 seconds,and it crosses a cyclist coming in opposite direction at 5km/h in 18 seconds. What is the speed of the train ?