Which of the following is $NOT$ a characteristic of the phylum $Annelida$?

Two vibrating tuning forks produce progressive waves given by $Y_1 = 4 \sin(500\pi t)$ and $Y_2 = 2 \sin(506\pi t)$. The number of beats produced per minute is:

The decreasing order of bond dissociation energies of $C-C$,$C-H$,and $H-H$ bonds is:

$A$ nichrome wire $50 \text{ cm}$ long and $1 \text{ mm}^2$ cross-section carries a current of $4 \text{ A}$ when connected to a $2 \text{ V}$ battery. The resistivity of the nichrome wire in $\Omega \cdot \text{m}$ is:

Which of the following statements is incorrect regarding viruses?

What is mycorrhiza?