Which of the following statements is wrong?A. Area of cross-section of nucleas in about 1 barn `(1 "barn" = 10^(-24)cm^(2))`B. Elements placed below the belt of stablility shwo positorn emission to increase their `(n)/(p)` ratioC. Elements placed above the belt of stablility show `beta-` emission to decrease their `(n)/(p)` ratioD. `K-` electron capture emits `gamma` rays.

Which of the following statements is wrong?A. Area of cross-section of

1.	Which of the following statements is wrong?A. Area of cross-section of nucleas in about 1 barn `(1 "barn" = 10^(-24)cm^(2))`B. Elements placed below the belt of stablility shwo positorn emission to increase their `(n)/(p)` ratioC. Elements placed above the belt of stablility show `beta-` emission to decrease their `(n)/(p)` ratioD. `K-` electron capture emits `gamma` rays.
Answer» Correct Answer - `(d)` `K-` electron caputre always give `X-` rays due to jump of electron from higher energy level to `K-` shell in order to fill the vacancy created by `K-` electron capture. `._(37)^(81)Rb + ._(-1)^(0)e overset("K-electron caputure")(rarr) ._(26)^(81)Kr + "X-ray"`

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