Which of the following has the lowest boiling point?

The accessory glands of the human male reproductive system are:

For a telescope,the focal length of the objective lens is $15 \ cm$ and the focal length of the eyepiece is $10 \ mm$. If the tube length is $16 \ cm$,find the magnification.

Cry $II$ Ab and Cry $I$ Ab produce toxins that control:

For a normal eye,the cornea of the eye provides a converging power of $40 \ D$ and the least converging power of the eye lens behind the cornea is $20 \ D$. Using this information,the distance between the retina and the cornea-eye lens can be estimated to be.......... $cm$.

This is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.