Sodium (Na) is a Alkali metal so that's the answer
AWhich of the following would most likely cause a decrease in the quantity supplied? A decrease in price.
The particles of the medium (slinky in this case) move up and down (choice #2) in a transverse wave scenario.
This is the defining characteristic of transverse waves, like particles on the surface of water while a wave travels on it, or like particles in a slack rope when someone sends a wave through by giving it a jolt.
The other kind of waves is longitudinal, where the particles of the medium move "left-and-right" along the direction of the wave propagation. In the case of the slinky, this would be achieved by giving a tensioned slinky an "inward" jolt. You would see that such a jolt would give rise to a longitudinal wave traveling along the length of the tensioned slinky. Another example of longitudinal waves are sound waves.
Answer:
Explanation:
Given
mass of lead piece 
mass of water in calorimeter 
Initial temperature of water 
Initial temperature of lead piece 
we know heat capacity of lead and water are 
and 
respectively
Let us take 
be the final temperature of the system
Conserving energy
heat lost by lead=heat gained by water
Answer:
20.2 seconds
Explanation:
The airplane (and therefore the crate) initially has no vertical velocity, so v₀ = 0 m/s.
The crate is in free fall, so a = -9.8 m/s².
The crate falls downward, so Δx = -2000 m.
Find: t, the time it takes for the crate to land.
Δx = v₀ t + ½ at²
-2000 m = (0 m/s) t + ½ (-9.8 m/s²) t²
t = 20.2 s
It takes 20.2 seconds for the crate to land.
