A quiet moment during a test is interrupted as a physics book falls from a table and strikes the floor. The reaction force to the force of the Earth pulling the book
downwards is
O the book hits the floor
O the floor pushes up on the book
O the book exerts an upward pull on the Earth
O the force of gravity on the book

f is prop to m1xm2 double m1 double force

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2