Mortar is a mixture of which of the following?

If $f(x) = \sin^2 \left( \frac{\pi}{8} + \frac{x}{2} \right) - \sin^2 \left( \frac{\pi}{8} - \frac{x}{2} \right)$,then the period of $f$ is

What are the substances which mimic the natural chemical messengers?

Consider the following statements:
$(I)$ The radius of an anion is larger than that of the parent atom.
$(II)$ The ionization energy generally increases with increasing atomic number in a period.
$(III)$ The electronegativity of an element is the tendency of an isolated atom to attract an electron.
Which of the above statements is/are correct?

The value of $\int_{-1}^{1} (\sqrt{1 + x + x^2} - \sqrt{1 - x + x^2}) \, dx$ is

The equivalent resistance between $A$ and $B$ is