The effectiveness duration of Cu-380 A from the day of insertion is ______ years.
A5 years
B10 years
C15 years
D7 years
A5 years
B10 years
C15 years
D7 years
Related Questions:
A Student focuses a sharp image of sun using a spherical mirror on a sheet of paper, which starts to burn after some time. Which of the following statement/statements about the mirror is/are correct?
a) It is concave spherical mirror
b) It is positive focal length
c)It is a converging mirror