Maximum bond angle is present in

An eight-digit number divisible by $9$ is to be formed using digits from $0$ to $9$ without repeating the digits. The number of ways in which this can be done is: (in $(7!)$)

If $4x^2 - 5xy + y^2 = 0$ represents a pair of lines with slopes $m_1$ and $m_2$,then the value of $|m_1 - m_2|$ equals

The mass defect in a particular nuclear reaction is $0.3 ~g$. The amount of energy liberated in kilowatt hour is: (Velocity of light $= 3 \times 10^8 ~m/s$)

If $\lim _{x \rightarrow \infty}\left(\frac{x^2+x+1}{x+1}-ax-b\right)=4$,then

If $3 \cos x \neq 2 \sin x$,then the general solution of $\sin^2 x - \cos 2x = 2 - \sin 2x$ is