Did Kepler propose the modern model of the solar system?

The graph shows two runners participating in a race. Which best describes the runners? Daniela had a 5 meter head start, and Leonard caught up to her at 25 meters. Daniela ran faster than Leonard through the entire race.

A tennis player hits a 1.45 kg tennis ball with a racket of mass 2.5 kg. If he hits the ball with a velocity of 7.5 m/s and then stops, what impulse did he imply on the ball? What is the ball's velocity?

Why would two poles of different magnets repel one another?

If the mass of an object increases, what also increases?

How does acceleration affect your average speed?

Why does it hurt your hands when you carry heavy shopping in carrier bags?

Why did scientists choose carbon as a base for the atomic mass unit? Which isotope of carbon did they use?

What organelle is found in all animal cells and some plant cells

Basic of Archimedes's principle of how fluid can make body to float and sink.

A bullet is accelerated down the barrel of a gun by hot gases produced in the combustion of gun powder. What is the average force (in N) exerted on a 0.0500 kg bullet to accelerate it to a speed of 625 m/s in a time of 1.10 ms (milliseconds)