Canada has a queen as its head of state , but also has a formal set of laws that is over seen by a parliament and a prime minister , this description is what type of government system

Gravity, from the center of mass of the box, extending downward normal force, from the floor under the box, extending upward, equal to gravity push force, acting at a point on the box, extending in the direction of motion friction, acting at any point on the box directly opposite the push, extending directly opposite to the motion

C) the periods  of day and night would be fixed all year for anyone at the  equator

Answera volcano just before it erupts