From your observation of the light patterns from 2, 3, 4, and 5 slits, guess the general formula for the number of secondary fringes as a function of the number of slits; i. e., for N slits (N >2) what is the number of secondary fringes

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?