How many of the given compounds will give a positive Biuret test ____________ ?

Glycine, Glycylalanine, Tripeptide, Biuret

The neutralization occurs when 10 mL of 0.1M acid 'A' is allowed to react with 30 mL of 0.05 M base M(OH)₂. The basicity of the acid 'A' is __________.

[M is a metal]

Let $$A = \{ x \in R:|x + 1| < 2\} $$ and $$B = \{ x \in R:|x - 1| \ge 2\} $$. Then which one of the following statements is NOT true?

Let a, b $$\in$$ R be such that the equation $$a{x^2} - 2bx + 15 = 0$$ has a repeated root $$\alpha$$. If $$\alpha$$ and $$\beta$$ are the roots of the equation $${x^2} - 2bx + 21 = 0$$, then $${\alpha ^2} + {\beta ^2}$$ is equal to :