Aprotostar is
1.a region of space from which light cannot escape
2.a small star that will continue as a main sequence star for hundreds of billions of years
3.a star with a core of neutrons
4.the stage after a star completes its main sequence existence
5.the stage before a star becomes a main sequence star

To run the physics cart, the fan speed of the cart is manipulated. this is the (blank) variable. the cart accelerates due to the speed of the fan. acceleration is therefore the (blank) variable. a “constant” is a parameter that stays the same regardless of the variables. one parameter of the cart that is held constant is the (blank) .

According to newton's second law, when the same force is applied to two objects of different masses, a the object with greater mass will experience a great acceleration, and the object with less mass will experience an even greater acceleration, b. the object with greater mass will experience a smaller acceleration, and the object with less mass will experience a greater acceleration, c. the object with greater mass will experience a greater acceleration, and the object with less mass will experience a smaller acceleration, d. the object with greater mass will experience a small acceleration, and the object with less mass will experience an even smaller acceleration.

What are the starting materials for nuclear fission? two small nuclei two large nuclei a neutron and a large nucleus a neutron and a small nucleus