Which of the following is an exception in terms of its life cycle?

The circumcentre of the triangle with vertices at $(-2, 3)$,$(1, -2)$ and $(2, 1)$ is

$10 \ g$ of a radioactive element is disintegrated to $1 \ g$ in $2.303 \ \text{minutes}$. What is the half-life (in minutes) of that radioactive element?

$A$ coil of self-inductance $L$ is connected in series with a bulb $B$ and an $A.C.$ source. Brightness of the bulb decreases when

In the case of small cuts,bleeding is stopped by applying potash alum. Here alum acts as

Which of the following is logically equivalent to $\sim(\sim p \Rightarrow q)$?