What causes a regular reflection?

What is the spinning rotation of a planet from east to west called?

A_ is made of one or more elements chemically bonded through electron sharing

I have completed 40 minutes of exercise today and will enter a short description in the course Activity Log. True or False

Which of the following would not be a good fuse design?

1.) Assuming the clay blob and the superball have the same mass, and that you throw them with the same velocity, which would you throw to close the door?

Technician A says that engine parts should be be cleaned before a thorough test can be done to detect cracks. Technician B says that pressure testing can be used to find cracks in blocks or cylinder heads. Who is right?

How are mathematics and science related?

Radio telescopes detect waves with a wavelength of roughly 10 m. True False

2. A 0.30 kg ball is dropped onto a concrete driveway. The ball's velocity before impact is 4.5 m/s and after impact is 4.2 m/s. What is the change in the ball's momentum?

If we start with 400 atoms of a radioactive substance, how many would remain after one half-life? After 2 half-lives? After 3 half-lives? After 4 half-lives?