Which of the following hydrides is electron-deficient?

Which of the following is a plasmid?

Which of the following ions forms the most stable complex compound?

Let $f(x)$ be a non-negative continuous function such that the area bounded by the curve $y = f(x)$,$x$-axis and the ordinates $x = \frac{\pi}{4}$ and $x = \beta > \frac{\pi}{4}$ is $\left( \beta \sin \beta + \frac{\pi}{4} \cos \beta + \sqrt{2} \beta \right)$. Then $f\left( \frac{\pi}{2} \right)$ is

How many $EDTA$ molecules are required to make an octahedral complex with a $Ca^{2+}$ ion?

If the circle $x^2 + y^2 + 2gx + 2fy + c = 0$ touches the $x$-axis,then: