(a) An atom Y has atomic number 12. It loses two electrons in order to be stable.
(i) State the proton number of the atom before it loses electrons.
(ii) State the electron number of the atom:
(α) before it loses electrons.
(β) after losing electrons.

(iii) Name the type of ion formed by the atom when it loses two electrons.

(b) Name four farming systems used in crop production.

(c) (i) What is dispersal of seeds?
(ii) State two characteristics of seeds dispersed by wind.

(d) Explain the term forward bias of a p-n junction diode.