WILL GIVE BRAINLIEST Which among the various techniques of stellar distance measurement is the best one? Discuss the merits and demerits of all the techniques (stellar parallax, using absolute and apparent magnitudes, using periods of variable stars, and red shifts of very distant objects).

Three point charges, two positive and one negative, each having a magnitude of 20 μc are placed at the vertices of an equilateral triangle (30 cm on a side). what is the magnitude of the electrostatic force on the negative charge

Which body part transports oxygen removes waste materials in carries nutrients to the body as part of the circulatory system

Simon is writing a story about an astronaut whose spacecraft has been boarded by space pirates. the astronaut has her lucky penny in her hand behind her back as the space pirates break into the control room. she has just locked the controls so that the ship is accelerating in the direction of the control room’s ceiling. simon wants the astronaut to use the penny to hit a button on the control panel to turn off the lights and escape. the button is located a short distance behind and below the astronaut’s hands. how should simon use the theory of relativity to describe what the astronaut must do in order to hit the button?