Define amu.

Calculate the molecular mass of CH_(4) molecule in amu.

One a.m.u. stands for

How many kilograms are there in 1 amu ?

One a.m.u. is equal to

Atomic weight of an element X is 120 when one amu is defined as 1//18th part by weight of an element of C^(12) . On the same scale, atomic weight of another element Y is 72. Which of the following statement regarding X and is (are) correct?