In which part will the deficiency symptoms of nitrogen and potassium first appear?

On the basis of symptoms of chlorosis in leaves,a student inferred that this was due to the deficiency of nitrogen. This inference could be correct only if yellowing of leaves appeared first in

Premature leaf fall is caused due to the deficiency of

In a $Citrus$ plantation,all the plants were found to be suffering from the die-back disease,and spraying of fungicides was of no help. This problem was due to the deficiency of:

Which mineral elements cause stunted growth when deficient?

Which deficiency causes the disease anemia?