Answer:
D) 13.62 kg/L
Explanation:
This problem can be solved by a simple rule of three.
The problem states that Mercury has a dansy of 30 lbs/L, and asks what is the density in kg/L. We have to convert from lbs to kg.
Each lb has 0.454 kg? How many kg are there in 30 lbs?
So:
1 lb - 0.454kg
30 lb - x kg


This means that mercury's density in kg/L is 13.62, letter D. Letter A is also 13.62, however it is not in the unit asked.
After the independence of many African countries (not all, for example, Ethiopia was never really colonized), the countries struggled both politically and economically - even more than before the independence.
A huge reason for that is that the countries were not formed along the ethnic lines, but instead they were divided by the Europeans among themselves, so when the independence was gained, there were many internal conflicts between the ethnicities and religions.
One example for this was the Rwandan Genocide - a result of the conflict between the Hutu and the Tutsi.
Answer:
B)Meteor showers are visible only in the northern hemisphere as the comets orbit over the Earth.
Explanation:
Meteor showers are visible only in the northern hemisphere as the comets orbit over the Earth. Stars and constellations appear throughout the sky, in both hemispheres. Meteors are visible everywhere, although some showers are more visible in certain parts of the night sky at specific times during the year.
Earth has the most density with 5.51 grams / cm^3