If $x$ is real,then the minimum value of $y = \frac{x^2-x+1}{x^2+x+1}$ is

$A$ charge of $1 \mu C$ is divided into two parts such that their charges are in the ratio of $2: 3$. These two charges are kept at a distance $1 \ m$ apart in vacuum. Then,the electric force between them (in $N$) is

$A$ fair coin is tossed $100$ times. The probability of getting tails an odd number of times is

$A$ tuning fork of frequency $392 \ Hz$ resonates with $50 \ cm$ length of a string under tension $T$. If the length of the string is decreased by $2\%$,keeping the tension constant,the number of beats heard when the string and the tuning fork are made to vibrate simultaneously is:

Who is known as the father of Indian Bryology?

The biquadratic equation,two of whose roots are $1+i$ and $1-\sqrt{2}$,is