the algebraic sum of the secondary forces must be equal to zero

the algebraic sum of the couples about any point in the plane of the secondary forces must be equal to zero

the algebraic sum of the secondary forces must be equal to zero and the algebraic sum of the couples about any point in the plane of the secondary forces must be equal to zero

none of these

at the origin

below the origin

above the origin

any one of these

remains constant

decreases

increases

none of these

to dip the nose and tail

to raise the nose and tail

to raise the nose and dip the tail

to dip the nose and raise the tail

two links

three links

four or more than four links

all of these