What is the velocity of a ball right before it hits the ground if it falls from a 2.5 m bookshelf?

Give one example to show that when substances are mixed,it may result in a chemical or a physical change depending on the conditions.

An astronaut floating in space is trying to use her jetpack to get back to her space station, but she is being pulled away by a nearby planet, as shown in the image below. her jetpack provides a constant thrust of 310 n. if she angles her jetpack in such a way that it cancels out the vertical force due to the planet's gravity, what is her net horizontal force? thaud 487 o a. 54.8 n toward the space station o b. 212.9 n toward the space station o c. 185.2 n toward the space station o d 956 n toward the space station

What is a analogy for transition metals