$\tan 9^{\circ}-\tan 27^{\circ}-\tan 63^{\circ}+\tan 81^{\circ} = $

Which characteristics are included in the Kingdom $Monera$?

The ends of a stretched wire of length $L$ are fixed at $x = 0$ and $x = L$. In one experiment,the displacement of the wire is $y_1 = A \sin(\pi x/L) \sin(\omega t)$ and the energy is $E_1$. In another experiment,its displacement is $y_2 = A \sin(2\pi x/L) \sin(2\omega t)$ and the energy is $E_2$. Then:

Excess of which of the following in water causes blue baby syndrome disease?

$A$ given system undergoes a change in which the work done by the system equals the decrease in its internal energy. The system must have undergone an

The $AT/GC$ ratio in human beings is (where $A=$ adenine,$T=$ thymine,$G=$ guanine,$C=$ cytosine).