Which of the following is best described as an inclined plane twisted into a spiral?
a.
a pulley
b.
a screw
c.
a wheel and axle
d.
a wedge

Organelles are 1. responsible for producing power for the cell 2. tiny structures in the cell that carry out the cell's activities 3. responsible for digestion in the cell 4. found outside of the membrane

For the car in the picture ,in which direction is the normal force? -into the screen -down -out of the screen -up

What are the necessary conditions for fusion?