In other words, normally added mass you represent as how many times mass it is, rather than just by number. You see it is a relative non dimensional wave; a coefficient; added mass is a unit of mass. So, easiest way to tell how much is added mass is of course, trying to tell how many times of the actual rigid body mass is added mass. So, you have a feel. So, this is how it is. So, alpha z that these plots are available for different value of say say different value of B n by t and this may be for. So, in other words if you see basically alpha z here as function of B n by t and beta n and of course omega. So, this versus this for, it is a three parameter thing. So, there is a family of curve available.