Which of the following statements is true?* A. Weight and mass are the same thing.
B. Weight is the gravitational force an object experiences due to its mass and
gravitational acceleration.
C. The weight of an object on Earth is less than the weight of the same object on the
moon, but the mass remains the same.
D. All of the above statements are true.

Natural forces that can alter ecosystems include seasons and climate changes. t or f

With the simplified model of the eye, what corrective lens (specified by focal length as measured in air) would be needed to enable a person underwater to focus an infinitely distant object? (be careful-the focal length of a lens underwater is not the same as in air! assume that the corrective lens has a refractive index of 1.62 and that the lens is used in eyeglasses, not goggles, so there is water on both sides of the lens. assume that the eyeglasses are 1.90

Point charges q1 = 51 µc and q2 = −27 µc are placed 1.0 m apart, with q2 on the right. what is the force (in n) on a third charge q3 = 19 µc placed midway between q1 and q2? (assume the positive direction is to the right. indicate the direction with the sign of your answer.)