Which characteristic of living organisms ensures that the population size of each species remains limited?

The lengths of tangent,subtangent,normal,and subnormal for the curve $y=x^2+x-1$ at $(1,1)$ are $A, B, C$,and $D$ respectively. Then their increasing order is:

The sum of the coefficients in the expansion of $(1+x+x^2)^n$ is

Which of the following is not a reducing agent?

Which one of the following is more readily hydrolysed by $S_{N}1$ mechanism?

The pairs of straight lines $x^2-3xy+2y^2=0$ and $x^2-3xy+2y^2+x-2=0$ form a