#1 A) Long wavelength and high frequency.
#2) A) Brightness.
#3) D) They are used to examine things.
#4) B) Compression and visible light waves.
Answer: 90 kgm/s
Explanation:
The momentum (linear momentum)
is given by the following equation:
Where:
is the mass of the skater
is the velocity
In this situation the skater has two values of momentum:
Initial momentum: 
Final momentum: 
Where:


So, if we want to calculate the difference in the magnitude of the skater's momentum, we have to write the following equation(assuming the mass of the skater remains constant):
Finally:
Full Question:
What is the Lewis structure of the covalent compound that contains one nitrogen atom, one hydrogen atom, and one carbon atom?
Explanation:
This covalent compound is the hydrogen cyanide, HCN.
The following steps are used to obtain it;
Step 1. Draw a skeleton structure of the compound based on the elements
Put the least electronegative atom C in the middle with H and Cl on either side.
H-C-N
Step 2. Count the valence (outermost) electrons you can use
H + C + N = 1 + 4 + 5 = 10
Step 3. Add these electrons to give every atom an octet
You have to put a triple bond between C and N.
Note: Each bond is made up of two electrons.
The lewis structure is given in the image below;
They are incline hope this helps!