Urgent !

a uniformly weighted ruler is placed on a balance. is all weight coming from the center of mass? does the section b have weight ?

Considering only the earth's rotation, determine how much later the asteroid would have had to arrive to put the explosion above helsinki at longitude 25˚ e? this would have obliterated the city.

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples

In which type of system is power held solely by the central government and not shared with regional governments? group of answer choices federal unitary confederate oligarchic