If the amplitude of sine curve is 4 and the frequency is 1 with no phase shift, what is the function that descirbes this curve?

The star betelgeuse is about 600 light-years away. if it explodes tonight, a. we'll know because debris from the explosion will rain down on us from space.b. we'll know it immediately because it will be brighter than the full moon in the sky.c. we won't know about it until 600 years from now.d. none of the above.

The dot diagram represents the motion of the motorcycle as it moves from left to right

If two students are running down the hall toward each other, trying to get to class, and they have the same mass and acceleration, what will happen when they collide? will their forces cancel out or will each one experience a reaction?