Pls I need help——— Balloon A is (A. Negatively, B. Not, C. Positively) charged, and balloon C is (A. Negatively, B. Not, C. Positively) charged. Balloon A approaches balloon C, there’ll be a force of (A. Attraction, B. Repulsion) between them.

Aforce of 200 n is applied to an input piston of cross-sectional area 2 sq. cm pushing it downward 2.8 cm. how far does the output piston of cross-sectional area 12 sq. cm move upward? show all work.

What are similarities and differences of reflection, refraction, diffraction and absorption?

Does anyone know how to solve this problem? i really need . i made an attempt but i just cant get it. a metal rod is 25.000 cm long at 25.0 degrees celsius. when heated to 102.0 degrees celsius, it is 25.054 cm long. what is the coefficient of linear expansion for this metal.