Making Constant Value for a particular Cell

A1 cell Value = 60000
B1 cell Value =  1
B2 cell Value  = 2

C1 cell value = A1*B1


In order to make a cell value as CONSTANT you got use $ as below.

For a cell named A1,
$A$1 should be used.

For C1 cell value = A1*B1

C1=  $A$1*B1.