Why do we see the color black?

I am having major trouble calculating the average speed for things. An example of a question would be, Rachel travelled 240 km in 4 hours by train and then travelled 120 km in 3 hours by car and 3 km in 1/2 hour by cycle.

A 0.023 kg beetle is sitting on a record player 0.15 m from the center of the record. If it takes 0.070 N of force to keep the beetle moving in a circle on the record, what is the tangential speed of the beetle?

To convert 790 kg/m3 to g/cm3, 1,000 and 106. These operations reveal that the density of acetone in g/cm3 is.

Are matter and weight the same thing?

What is the bond angle between two hydrogen atoms in an ammonia (NH3) molecule?

Describe how the Catapult works?

Anything dissolved in water

Length of two cylinders are measured to be L1 = 5.62 + / - 0.01cm and L2 = 4.34 + / - 0.02cm. calculate difference in error and error limit.

If you push an object twice as far while applying the same force, you do ...

Jane, looking for tarzan, is running at top speed (5.2 m/s) and grabs a vine hanging 4.5 m vertically from a tall tree in the jungle. how high can she swing upward?