When the pollen tube enters the ovule through the integuments,the process is known as?

$A$ bag contains $5$ black balls,$4$ white balls,and $3$ red balls. If a ball is selected at random,the probability that it is a black or red ball is

$A$ rod of mass $M$ and length $l$ is suspended by two wires $P$ and $Q$. $A$ uniform magnetic field $B$ is directed into the page. When current $I$ flows through the rod,the tension in each supporting wire is:

$A$ certain quantity of water cools from $70\,^{\circ}C$ to $60\,^{\circ}C$ in the first $5\, \text{minutes}$ and to $54\,^{\circ}C$ in the next $5\, \text{minutes}$. The temperature of the surroundings is ......... $^{\circ}C$.

If $\tan A + \cot A = 4,$ then $\tan^4 A + \cot^4 A$ is equal to

Which of the following is known as 'Oxone'?