C-12 and C-14 are examples of isotopes of carbon. They have the same atomic number (6, which means 6 protons) but different mass numbers, as C-12 has 6 neutrons and C-14 has 8 neutrons. This difference in neutrons makes them isotopes, which are atoms of the same element with different numbers of neutrons.
From the given following (A to D) cyclic structures, those which will not react with Tollen's reagent are : 
Compound 'P' undergoes the following sequence of reactions : (i) NH₃ (ii) $\Delta$ $\rightarrow$ Q (i) KOH, Br₂ (ii) CHCl₃, KOH (alc), $\Delta$ $\rightarrow$ NC-CH₃. 'P' is : 

Consider the following statements: Statement I: \( 5 + 8 = 12 \) or 11 is a prime. Statement II: Sun is a planet or 9 is a prime.
Which of the following is true?
The value of \[ \int \sin(\log x) \, dx + \int \cos(\log x) \, dx \] is equal to
The value of \[ \lim_{x \to \infty} \left( e^x + e^{-x} - e^x \right) \] is equal to