Write a single Ruby demo program that illustrates the use of all main Ruby iterators (loop, while, until, for, upto, downto, times, each, map, step, collect, select, reject). The program should have a few lines illustrating loop, followed by a few lines illustrating while, and so on).

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false

At 12 noon, the count in a bacteria culture was 400; at 4: 00 pm the count was 1200 let p(t) denote the bacteria cou population growth law. find: (a) an expression for the bacteria count at any time t (b) the bacteria count at 10 am. (c) the time required for the bacteria count to reach 1800.

The thermal expansion or contraction of a given metal is a function of the f a)-density b)-initial temperature c)- temperature difference d)- linear coefficient of thermal expansion e)- final temperature f)- original length