Palisade parenchyma is absent in leaves of

The vestigial stomata are present in

Usually the lower surface of a $...$ leaf has a greater number of stomata while in a $...$ leaf they are about equal on both surfaces.

In monocotyledonous leaves:

Large,empty,colourless cells present on the upper surface of grass leaves are known as:

The epidermis in a dorsiventral leaf:
$(a)$ Covers both adaxial and abaxial surfaces
$(b)$ Is not covered by cuticle
$(c)$ Bears more stomata on the upper side
$(d)$ May even lack stomata on the upper side
Which of the above statements are correct?