10 'Solution by Newton Raphson method
20 SCREEN 0,0,0:CLS
30 PRINT "Initial conditions : "
40 PRINT "Initial Gas Chamber Pressure (P3 = P2) = 15.3 Kg/cm2 a"
50 PRINT "Equiv. length L1(liq) = 125 ft; L2 (gas) =  48 ft"
60 PRINT "Dia. d1(liq) = 1.61 in. ; d2 (gas) = .5 in."
70 PRINT "Initial gas chamber volume : .15 m3"
80 'INPUT "Enter the Dia d1 (inches) :";D1
90 'INPUT "Enter the dia d2 (inches  :";D2
100 'INPUT "Enter the equvalent lenght L1 (ft) :";L1
110 'INPUT "Enter the equvalent lenght L2(ft)  :";L2
120 IF INKEY$="" THEN 120
130 D1=1.61:D2=.5:L1=125:L2=48
140 K1=(16.2/((6018)^2))+(4.54*(10^-8)*L1/(100*(D1^5)))
150 K2=(1/K1)^.5
160 K3=3.1863*(10^-6)*L2/(100*(D2^5))
170 K4=(1/K3)^.5
180 V=.15:R=8.910001E-02:TE=324:Z=1!:M=30:P2=15.3:C2=2.295
190 CLS:PRINT "Time             P3           Wl            Wg            P1           PD"
200     PRINT " (s)           (Kg/cm2 a)   (Kg/hr)       (Kg/hr)       (Kg/cm2 a)  (Kg/cm2)"
210 FOR T=0  TO 20/3600  STEP .1/3600
220 A=15.2
230 IF COUNT >20 THEN 240 ELSE 270
240 IF INKEY$="" THEN 240
250 COUNT=0:CLS:PRINT "Time             P3           Wl            Wg            P1           PD"
260     PRINT " (s)           (Kg/cm2 a)   (Kg/hr)       (Kg/hr)       (Kg/cm2 a)  (Kg/cm2)"
270 DEF FNA(P)=(K2*T/3000)*(5*P+1.8)*((P+.9)^(.5))-K4*(R*TE*Z/M)*T*((P2-P)^(.5))+V*P-C2
280 DEF FNA2(P)=(K2*T/3000)*((5*P+1.8)/(2*SQR(P+.9))+5*((P+.9)^(.5)))+K4*(R*TE*Z/M)*T*.5*((P2-P)^(-.5))+V
290 FUNA=FNA(A)
300 FUNB=FNA2(A)
310 H=-FUNA/FUNB
320 IF H<.00001 THEN ROOT = A :GOTO 350
330 A=A+H
340 GOTO 270
350 WL=((ROOT+.9)^.5)*K2
360 WG=((P2-ROOT)^.5)*K4
370 P1=(WL^2)*16.2/(6018^2)
380 PD = P1-ROOT
390 PRINT ST,ROOT,WL,WG,P1;"   ";PD
400 ST=ST+.1:COUNT=COUNT+1
410 NEXT 'END