Answer:
Because the kind of compounfds that you try to determine using paper chromatography (organic compounds) are usually not soluble in water. Furthermore, water could react chemically with some of this compounds, because it's a very reactive molecule. You need organic solvents that are mostly inert.
The horizontal line has equation 
. The line is solid, and everything below it is shaded, which translates to the inequality 
. (so not B nor D)
The dashed line must have equation 
. Because it's dashed, the inequality is strict. Pick any point in the shaded region, (0, 0) for instance, and compare both sides of this equation. (0, 0) means both 
and 
, so on the left side we have 0, and on the right we have -1. 0 > -1, so the inequality must be 
.
This means the answer is A.
Answer:
C. 17 miles
Step-by-step explanation:
Divide 68 by 4 since it is a fourth of an hour
Answer:
21.75
Step-by-step explanation:
If A onto B is 1 : 7.25 then you would do A times 7.25 to find the corresponding side. 3 times 7.25 is 21.75
