Q. Illustrate the relationship between Time and cost?

In software projects, time cannot be freely exchanged against cost. Such a trade off is limited by the nature of the software development. For a given organization, developing software of size S, the quantity obtained is constant. We know

K_1/3 t_d4/3 =S/C

If we raise power by 3 afterwards Kt_d4 is constant for constant size software. A density of the development time t_d will produce an increase of manpower cost. If compression is excessive not merely would the software cost much more, but as well the development would become so difficult that it would increase the risk of being unmanageable.