Carbon isotope evidence from rocks found on an island off the coast of Greenland, although controversial, suggests that life may have
A) existed and was well established by3.4 to 3.5 billion years ago
B) originated about 3.4 billion years ago
C) existed 3.85 billion years ago
D) originated when the Earth formed 4.6 billion years ago
C
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Two pipes are smoothly connected together without leaks. One has a diameter of 3 cm and the other has a diameter of 5 cm. Water flows through the pipes. In which pipe is the volume flow rate the greatest?
1.in the pipe that the water flows through first (the "upstream" pipe) 2.in the 3 cm pipe 3.in the 5 cm pipe 4.in neither, the flow rate is the same in both pipes
The difference between speed and velocity is that ________
A) velocity is calculated using a physics equation B) velocity is the same as acceleration but speed is different C) they are expressed in different units D) velocity also includes a direction
Acceleration: If the acceleration of an object is zero, then that object cannot be moving.
A. True B. False
Charge of uniform density (80 nC/m3) is distributed throughout a hollow cylindrical region formed by two coaxial cylindrical surfaces of radii 1.0 mm and 3.0 mm. Determine the magnitude of the electric field at a point which is 2.0 mm from the symmetry axis
a. 7.9 N/C b. 9.0 N/C c. 5.9 N/C d. 6.8 N/C e. 18 N/C