The number of sides in a decagon is `(l+15)/2`. The value of l is

The number of diagonals in a decagon is

If the standard deviation of the numbers -1, 0,1,k is sqrt(5) where k gt 0 , then k is equal to 2 sqrt(l) . The value of l is ________.

Quantum number is address of an electron in amy atom . They are of four types : Principal quantum number (n) Azimuthal quantum number (l) (c ) Magnetic quantum number (m) (d) spin quantum number (s) prinicial quantum (n) : (a) Denoted by n. (b) it can have any positive interger values like 1,2,3,........... Azimuthal quantum number or angulart momentum quantum number or subsidiary quantum number (l) (a) Denoted by l. (B) l can have any value from 0,1,2,... to (n-1) for each value of n {:( "value of l",0,1,2,3,4,5),("Notation of subshell",s,p,d,f,g,h):} MAgnetic quantum number (m or M_(l) ): (a) Denoted by m or m_(1) (B) it can have any value from -l to +l inckluding 0, for each value of l. Spin quantum number (s or m_(s) ) : The value of s is +(1)/(2) and -(1)/(2) which two quantum spin states . Maximum number of electrons in Na with l=0:

Let nge4 be a positive integer and let l_(1),l_(2),.....,l_(n) be the lengths of the sides of arbitrary n-sided non-degenerate polygon P. Suppose l_(1)/(l_(2))+l_(2)/(l_(3))+....l_(n-1)/(l_(n))+l_(n)/(l_(1))=n. Consider the following statements: I. The lengths of the sides of P are equal. II. The angles of P are equal. III. P is a regular polygon if it is cyclic. Then

The possible number of orientations of a sun-shell is (2 l + 1) The possible number of electrons in a sub-shell is (4 l + 2) .

Find the number of diagonals of (i) a hexagon, (ii) a decagon, (iii) a polygon of 18 sides.