How is dihydrogen obtained from

How is dihydrogen obtained from
(i) dilute sulphuric acid
(ii) sodium hydroxide
(iii) water? Give one equation in each case.

(i) When metal reacts with dilute sulphuric acid, hydrogen is obtained along with metal salts.

(ii) When zinc reacts with sodium hydroxide, sodium zincate is formed and hydrogen gas is evolved.

(iii) When acidified water is electrolysed using platinuni electrodes, hydrogen gas is evolved at cathode.