Algebra

Translate each of the following statements into an equation:
(a) The perimeter (p) of an equilateral triangle is three times of itsside (a).
(b) The diameter (d) of a circle is twice its radius (r).
(c) The selling price (s) of an item is equal to the sum of the costprice (c) of an item and the profit (p) earned.
(d) Amount (a) is equal to the sum of principal (p) and interest (i).