1. Describe the universal gravitational law. 2. Evaluate the techniques and models used by Ptolemy and Copernicus to explain the setup of the universe.

3. A child picks up a tennis ball tied to the end of a rope. He swings the rope around, over his head, in a circle. Once the ball is spinning, he lets go of the string and the ball goes flying. Explain which of the following images correctly shows which way the ball will fly and why.

Iwould have to say sorry i can't elaborate more. hope this though!

Jenny and fred both play a long note on their trombones. a stationary observer hears the sound increasing and decreasing repeatedly in loudness. which of these must be true? the sound waves from the two trombones have slightly different frequencies.the sound waves from the two trombones have the same frequency.the sound waves from the two trombones have slightly different amplitudes.the sound waves from the two trombones have the same wavelength.the sound waves from the two trombones have slightly different velocities.  lolthe answer is          the sound waves from the two trombones have slightly different frequencies.