Have you observed material used to make school bell or bells in temple?

What is the material used to make stethoscope?

What material is used to make handles of utensils ?

Have you observed the rare view mirrors of a car ?

Have you observed the colour of a cloud before its rain?

Have you ever observed the duration of anger ?

What material should be used to make the bottle opener ?

Have you ever observed details in the prescription ?

What have you observed about the main groups?

Have you observed tea being prepared? What substance are used for preparing tea? List them in table 7. and also list out the different substance that are used to make the items given in table7.

What type of material can you use to make a window when you want to see through it ?