Which of the following is true regarding the image provided?
Read the following statements: Statement I: All vertebrates develop a row of vestigial gill slits during embryonic stage.
Statement II: Embryos always pass through the adult stages of other animals.
A wooden block of mass M lies on a rough floor. Another wooden block of the same mass is hanging from the point O through strings as shown in the figure. To achieve equilibrium, the coefficient of static friction between the block on the floor and the floor itself is