There are 8 elements that together make up 98.5% of earth crust oxygen 46.6% aluminum 8.1% iron 5.0% calcium 3.6% sodium 2.8% potassium 2.6% magnesium 2.1% and silicon what percentage of earth crust is silicon

A 12 cm radius air duct is used to replenish the air of a room 9.2 m x 5.5 m x 4.5 m every 10 min. how fast does the air flow in the duct?

What is the Primacy Effect? Question 1 options: (a) The tendency of people to like winning more than losing (b) The tendency for items at the beginning of a list to be recalled more easily than other items.

Materials such as oil and gas are used as fuel because they have what chemical property?

Imagine the current in a current-carrying wire is flowing into the screen. What is the direction of the magnetic field around this current? The magnetic field is clockwise. The magnetic field is counterclockwise.

What is the approximate energy of a photon having a frequency of 5 x 10^-24 hz? (h=6.6 x 10^-34 j-s) ?

A student uses an indicator to measure the pH of a solution. The indicator shows a pH of 7. What must be true of this solution? The solution contains neither hydronium ions nor hydroxide ions.

What is the purpose of a valve?

A particle travels 15 times around a 10-cm radius circle in 42 seconds. what is the average speed (in m/s) of the particle?

Where are the magnetic fields stronger near a bar magnet? A) Top B) Center C) Ends D) Bottom

You pull a simple pendulum of length 0.225m to the side through an angle of 3.50∘ and release it. Part A How much time does it take the pendulum bob to reach its highest speed? Take free fall acceleration to be 9.80 m/s^2.