vol of sphere

DATA SEGMENT
RADIUS DD 5.0
CONSTANT DD 1.33
VOL DD 01 DUP (?)
DATA ENDS

CODE SEGMENT
ASSUME CS:CODE,DS:DATA

START:  MOV AX,DATA
        MOV DS,AX

        FINIT
        FLD RADIUS
        FST ST(4)
        FMUL ST(0),ST(4)
        FMUL ST(0),ST(4)
        FLD CONSTANT
        FMUL
        FLDPI
        FMUL
        FST VOL

QUIT:   MOV AX,4C00H
        INT 21H
CODE ENDS
END START