निम्न को सुमेलित कीजिए -

Answer

(A)-q,t; (B)-p,r,s; (C )-p,r,s; (D)-p,r,t

Explanation

(A) `(1)/(f)=underset(-)ubrace(((n_(l))/(n_(s))-1))" "underset(+)ubrace(((1)/(R_(1))-(1)/(R_(2))))`
`f=-ve`
`P=(1)/(f)= -ve" "q,t`
(B) `(1)/(f)=underset(+)ubrace(((n_(l))/(n_(s))-1))" "underset(+)ubrace(((1)/(R_(1))-(1)/(R_(2))))`
`f=+ve`
`P=(1)/(f)= +ve" "p,r,s`

(C ) `(1)/(f)=underset(-)ubrace(((n_(l))/(n_(s))-1))" "underset(-)ubrace(((1)/(R_(1))-(1)/(R_(2))))`
`f= +, P=(1)/(f)= +ve " "p,r,s`
(D) `f=(R )/(2)`
`P=(1)/(f)= -ve " "r,q,t`