Which of the following types of stars are dim but can have high surface temperatures?

a.) giants
b.) main sequence stars
c.) supergiants
d.) dwarfs

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?

What is the major limitation to the light microscope?

Which of the following describe possible scenarios? a) an object has zero instantaneous velocity and non-zero acceleration. b) an object has negative acceleration and is speeding up. c) an object has positive acceleration and constant velocity. d) an object has positive velocity and zero acceleration. e) an object has increasing positive position and negative velocity. f) an object has decreasing positive position and negative acceleration.