The figure shows a system of logic gates. From the study of the truth table,it can be found that to produce a high output $(1)$ at $R$,we must have

In the process of transcription,the sigma factor is important for:

$A$ bullet of mass $10 \ g$ pierces through a plate $A$ of mass $500 \ g$ and then gets embedded into a second plate $B$ of mass $1.49 \ kg$ as shown in the figure. Initially,the two plates $A$ and $B$ are at rest and move with the same velocity after the collision. The percentage loss in the initial kinetic energy of the bullet,when it is between the plates $A$ and $B$,is . . . . . .
(Neglect any loss of material of the plates during the collision)

When a wave travels in a medium,the particle displacement is given by: $y = a \sin 2\pi (bt - cx)$,where $a, b$,and $c$ are constants. The maximum particle velocity will be twice the wave velocity if

What is absent in yeast?