The equation $\sqrt{3} \sin x + \cos x = 4$ has

$A$ lift is moving downwards with an acceleration equal to the acceleration due to gravity. $A$ body of mass $M$ kept on the floor of the lift is pulled horizontally. If the coefficient of friction is $\mu$,then the frictional resistance offered by the body is:

Let $a, b, x, y$ be real numbers such that $a^2+b^2=81$,$x^2+y^2=121$ and $ax+by=99$. Then,the set of all possible values of $ay-bx$ is

Which of the following is a class of $Bryophytes$?

Which of the following is not a peroxo acid?

Diazo-coupling is useful to prepare some