Magnetism and Matter

By removing the inducing magnet, the induced magnetism is
Which power supply can be used in electric bell
The magnetic susceptibility for a diamagnetic substance decreases with the increase in temperature.

Two short bar magnets with magnetic moments $$8$$ $$Am^2$$ and $$27$$ $$Am^2$$ are placed $$35$$ $$cm$$ apart along their common axial line with their like poles facing each other. The neutral point is :

Two magnets when placed in $$\tan A$$ position at the same distance cause deflections of $$30^{o}$$ and $$60^{o}$$. The ratio of their magnetic moments is :