Write down a c program which creates a child process and prints hello message from child and parent both. Also use wait system call

Which database model is best used for data warehouse and data mining

Least square fit to polynomial write a function leastsquarefit3pol that solves a linear system of equations to find a least squares fit of a third order polynomial to an experimental data set given as two row arrays. the function leastsquarefit3pol must explicitly solve a set of linear equations and cannot use polyfit. there should be no restriction on the size of the problem that can be solved.

What are three software programs for mobile computing?