Within a DNA molecule, which two nitrogen bases are correctly paired with one another?

A. cytosine (C) and uracil (U)

B. adenine (A) and thymine (T)

C. adenine (A) and guanine (G)

D. cytosine (C) and thymine (T)

A train approaching a crossing changes speed from 25 m/s to 10 m/s in 240 s. How can the train's acceleration be described?

What determines the strength of the electric force?

The temperature of a sample of water increases from 20°c to 46.6°c as it absorbs 5650 calories of heat what is the mass of the sample?

A question about a moral issue is answered by examining facts rather than opinions. is generally considered a scientific question. cannot be answered with scientific methods. cannot be debated through discussion.

Why do satellites in orbit fall to the ground? why dont they fly into space?

How does the strong nuclear force compare with the electrostatic force in the nucleus of an atom? A. The strong nuclear force is stronger and is only attractive. B. The strong nuclear force is weaker and acts over longer distances. C.

A 1100 - kg car collides with a 1300 - kg car that was initially at rest at the origin of an x-y coordinate system. After the collision, the lighter car moves at 20.0 km/h in a direction of 30 o with respect to the positive x axis.

Which of the following is the best definition of an isotope? A. elements of the same kind with different numbers of neutrons B. elements of the same kind that have lost electrons C. elements of the same kind that have different electrical charges

A light plane must reach a speed of 33m/s for takeoff. how long a runway is needed if the the acceleration is 3.0m/s^2

How do astronomers learn about the internal structure and evolution of stars? How does a new star form? What causes a supernova to occur? Explain. Is the lifetime of a massive star shorter or longer than a star like the Sun? Why?