Construct a square, if :
(i) its one side is 3.8 cm
(ii) its each side is 4.3 cm.
(iii) one diagonal is 6.2 cm.
(iv) each diagonal is 5.7 cm.
△ABC is constructed such that AB = 7 cm, AC = 4 cm and ∠A = 75∘. Then the length of side BC is