Scientists believe true commensalism may not exist because . the second organism is probably helped or harmed in unknown ways
parasites are most likely helping their hosts in subtle ways
most organisms prefer to compete and do not like to help each other
evolution and adaptation keep the organisms from killing each other

Scientists believe true commensalism may not exist because

mostly all organisms live in either parasitic or mutual relationship.

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

pythagoras' theorem

square root (-5^2+9^2)

square root (25+81)

square root (106)

angle is tan^-1(9/5)

neg x, pos y