John made a stethoscope using a paper cup and plastic tube. Write down the procedure he followed.

John prepared stethoscope with paper cup and plastic tube. Write down the procedure of preparation?

Write down all the subsets of the following sets {a}

Write down all the subsets of the following sets phi

Write down all the subsets of the following sets {a,b}

Write down all the subsets of the following sets {1,2,3}

Who discovered the cell for the first time? What procedure did he follow ?

Sameer wants to observe Rhizopus under microscope. For this i) What are preparatory activities he has to do? ii) What procedure does he follow? And iii) What precautions should he take?

Taking the set of natural numbers as the universal set, write down the complements of the following sets: { x : x is a positive multiple of 3}

Taking the set of natural numbers as the universal set, write down the complements of the following sets: { x : x is a perfect square }

Taking the set of natural numbers as the universal set, write down the complements of the following sets: { x : x is a perfect cube}