What is the conductivity of 0.05 M KCl solution if cell constant is $1.32 \mathrm{~cm}^{-1}$ and resistance is 528 ohm?

Which of the following substances conducts electricity?

$\int_\limits0^{\frac{\pi}{2}}|\sin x-\cos x| d x$ has the value

Negation of the statement "The payment will be made if and only if the work is finished in time." is