Questions

Production costs to an economist reflect opportunity costs.

A trampoline is a sheet or web supported by springs in a metal frame and is used as spring board.

We know that, peninsula is a piece of land that surrounded by water on three sides.  Hence, it is what A piece of land almost surrounded by water i.e, three sides water and one side land.

The preamble to the constitution does not specify providing for economic equity.

Here ‘passed each other’ means crossed each other’s path. No preposition is required by ‘passed’.

Gene is a hereditary unit consisting of a sequence of DNA that occupies a specific location on a chromosome and determines a particular characteristic in an organism.

In short it is a piece or segment of chromosome.

Genes undergo mutation when their DNA sequence changes. 

In Spain, where there were no protestants, a soldier named lgnatius Loyola started an organisation for clergymen to work wholly as 'soldiers of jensus' in the service of the Church. Its members came to be called jesuits. They went from place to place and won back followers in France and Germany. They established missions in india, china, Africa and the Americas to gain new adherents. The Jesuit Schools which they started to strengthen the Roman Catholic  Church are still in existence in many countries of the world.