28 
d.z TZ45- Zo5- 2Lzji- 2Lz, + 4Lz,;+ 22,5 
e = -Zı57 Zg5- 2Lz,g- 2Lzogt 4Lzg ot 2zg 
f -Lzj,- Lzg,+ Lz, gt Lzggt 2Lz.|- éLz,9 
4 77Psj-Pag* 4Pgg .. t 5 -Lz5,- Legot 225, 
Fr EAP Pye a mz gnlepn i9 
& 7 29957. P917 P99 VP AAggz bol riUigg 
  
  
e. X 
2 m. {6(at+rutsv)+ad+be+ct} ^ 
6(t"*u t )ed re^ H^ 
o 
1 
© 
T 
Ut 
wn 
Confidence limits. 
For confidence level 5 per cent: 0.6 509" 2.9 Sg 
- 4,4 80 
9 
9 
n " n ] per cent: 0.5 s 
09