Which of the following oxides is amphoteric in nature?

Which statement is wrong for viruses?

Let $u = i + j$,$v = i - j$ and $w = i + 2j + 3k$. If $n$ is a unit vector such that $u \cdot n = 0$ and $v \cdot n = 0$,then $|w \cdot n|$ is equal to

If $\theta$ is the angle between the curves $xy=2$ and $x^2+4y=0$,then $\tan \theta$ is equal to:

The number of $5$-digit numbers that are not divisible by $5$ and consist of different odd digits is:

The solution of $(x^2+y^2) dx = 2xy dy$ is: