9. A natural phenomenon showing seven colours of light._____10. The mid-point of the line joining the polesand optical centre of the lens.________

9. A natural phenomenon showing seven colours of light._____10. The

1.	9. A natural phenomenon showing seven colours of light._____10. The mid-point of the line joining the polesand optical centre of the lens.________
Answer» 9.rainbow 10.concave LENS