ISOLATION OF ELEMENTS - L9

L-6 to L-9

L-9 to L-11

Let A={n in N : n is a 3- digit number } B={ 9k +2 : k in N} and C= { 9k +l : K in N } for some l (0 lt l lt 9) if the sum of all the elements of the set A nn (B uu C) is 274 xx 400 , then l is equal to ______.

Consider a regular 10-gon with its vertices on the unit circle. With one vertex fixed, draw straight lines to the other 9 vertices. Call them L_1 , L_2 ,…, L_9 and denote their lengths by l_1 ,l_2 ,…, l_9 respectively. Then the product l_1 , l_2,...,l_9 is

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is :

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is : The valency of element is

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is : The total number of s electons are

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is : The total number of p electons are

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is : The total number of d electons are

A natural atom of an element has 2K,8L, 9M and 2N electrons .The atomic number of element is : The total number of unpaired electons are