Persistent nucellus in the seed is known as

$A$ three-digit number $n$ is such that the last two digits are equal and differ from the first digit. The number of such $n$'s is:

Which of the following is the correct statement for the given reaction?
$CH_3-CH=O + C_6H_5-CH=O \xrightarrow[\Delta]{OH^{-}_{(aq)}} X (C_4H_6O) + Y (C_9H_8O)$

In a $\triangle ABC$,the expression $\frac{\cos C+\cos A}{c+a}+\frac{\cos B}{b}$ is equal to

The cyanobacteria are also referred to as

What does an $ECG$ measure?