In a stem which is covered by periderm and in which stomata are absent,gaseous exchange takes place through

In a stratified cambium,the fusiform initials are

Vascular cambium is a meristematic layer that cuts off

The anatomy of springwood shows some peculiar features. Identify the correct set of statements about springwood.
$(a)$ It is also called as the earlywood
$(b)$ In spring season cambium produces xylem elements with narrow vessels
$(c)$ It is lighter in colour
$(d)$ The springwood along with autumnwood shows alternate concentric rings forming annual rings
$(e)$ It has lower density
Choose the correct answer from the options given below:

The vascular cambium produces . . . . . . .

$A$ nail is driven into the trunk of a $30$ year old tree at a point $1$ meter above the soil level. The tree grows in height at the rate of $0.5$ meters a year. After three years,the nail will be