Why is the colour of a leaf in the dark frequently turns yellow, or pale green ? Which pigment do you think is more stable ?

A plane glass plate is placed over a various coloured letters ( violet , green , yellow , red ) . The letter which appears to raised more is

Total number of students of a school in different years is shown in the following table B Prepare another pictograph of students using any other symbol each representing 50 students. Which pictograph do you find more informative?

We use colours dissolved in water during Holi and clothes gets spoiled. Many colours used to celebrate Holi are oxidized metals or industrial dyes mixed with engine oil. Doctors say these are harmful colours which should be banned for usage. Manufactures mix dyes with colours, and sell them for their profits. Holi lovers can make their Holi colourful by using natural colours available in the market.Natural colours start fading when they come in contact with sun rays. (i) Why doctors say that synthetic colours are harmful? (ii) What are natural colours? (iii) As a student what initiative you will take to motivate your classmates to use natural colours in Holi? Give any suggestions.