Answer:
The answer is A. Polar covalent; negatively
Explanation:
Hydrogen bonds form between molecules containing polar covalent bond the hydrogen bond is been a hydrogen atom of one molecule and a partially negative charged atom of another.
Example 
(water):- It contain a slight positive charge on one side and a slight negative charge on the other.
The pressure that will be exerted if four sample of gas are placed in a single 3.5 container is calculated as below
if each gas occupies 675 mmhg
what about 4 gases in the sample
by cross multiplication
= 675 mm hg x 4/1 = 2.7 x10^3mmhg (answer D)
Describe the process by which Ag+ ions are precipitated out of solution. 4. In your testing, several precipitates are formed, and then dissolved as complexes.
speed equals wavelength times frequency so
.7 x 500 = 350
I’m not to sure but let me figure it out hold up
