Answer:
Magnification will be equal to 3
Explanation:
We have given focal length of the converging lens 
Focal length of the diverging lens 
Object is placed 40 cm to the length of the converging lens d = 40 cm
Combination of the focal length will be equal to


F = 60 cm
So combination of the focal length will be 60 cm
Magnification is given by

So magnification will be equal to 3
Why is it always balloons?
anyways so the balloon volume goes somewhere else when it shrinks because the balloon is losing air i think
Well minerals are in the water we drink every Day, even the food we eat. Minerals are contained in rocks so there for both are important to life