Mendel published his work on inheritance of characters in 1865 butit remained unrecognised till 1900 because
(a) He could not provide any physical proof for the existance of factors
(b) His concept of factors as stable, discrete units that acceptance from the contemporaries
(c ) Mendel's approach of using approach of using mathematics to explain biological phenomena was totally old
(d) Communication was not easy (as it is now)

Explanation

For lamp`i=(5)/(20)=0.25A`
`R=(20)/(0.25)=80Omega`
Current through the lamp should be 0.25 A
(a) When condenser C is placed in series`i=(200)/sqrt(R^(2)+(1)/(omegaC)^(2))=0.25`
putting the value of `omega=2pixx50` `thereforeC=4.0muF`
(b) When inductor is used`I=(200)/(sqrt(R^(2)+(omegaL)^(2)=0.25impliesL=2.53H`
(c) When resistance is used`I=(200)/(R+r)=0.25`
`impiiesr=720Omega`