Applied Mechanics and Graphic Statics
The characteristic of a couple is:

All listed here
Algebraic sum of forces, constituting a couple is zero
A couple can be never the balanced by a single force
Algebraic sum of moments of forces, constituting a couple, about any point, is same

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
A ball which is thrown upwards, returns to the ground describing a parabolic path during its flight

Speed of the ball remains constant
Kinetic energy of the ball remains constant
Horizontal component of velocity remains constant
Vertical component of velocity remains constant

ANSWER DOWNLOAD EXAMIANS APP