Chromosome number can be doubled by using which of the following?

Where are the following hormones synthesized in plants?
$(a)$ $IAA$
$(b)$ Gibberellins
$(c)$ Cytokinins

Plants which behave as mesophytes in rainy season and as xerophytes in summers are called:

$A$ sleep movement in plants is a nastic response that occurs daily in response to

Study the following statements.
$I.$ "$X$" hormone promotes root growth and root hair formation, thus helping the plants to increase their absorption surface.
$II.$ "$Y$" hormone induces flowering in mango and also promotes rapid internode/petiole elongation in deep-water plants, hence helping leaves or upper parts of the shoot remain above water.
$III.$ "$Z$" hormone inhibits seed germination, increases the tolerance of plants to various stresses, and plays an important role in seed development, maturation, and dormancy.
Identify the correct names of hormones marked as $X$, $Y$, and $Z$.

$I.$ Auxin,$II.$ Cytokinin,$III.$ $GA$,$IV.$ $ABA$.
Which of the above-mentioned $PGR$ are acidic in nature? Choose the correct option accordingly.