What is the foundation of any breeding program?

Which of the following tissues is present in the leaves of $Pinus$ and serves to conduct water and food?

On heating one end of a rod,the temperature of the whole rod will be uniform when

Light of wavelength $\lambda$ is incident on a single slit of width $a$ and the distance between the slit and the screen is $D$. In the diffraction pattern,if the slit width is equal to the width of the central maximum,then $D$ is equal to:

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

$A$ charge $Q$ is enclosed by a Gaussian spherical surface of radius $R$. If the radius is doubled,then the outward electric flux will