Answer: 28.40
Explanation:
For A(27.977 u)
Mass number = 27.977
Abundance = 78.21%
For B (28.976 u)
Mass number = 28.976
Abundance = 1.346%
For C(29.974 u)
Mass number = 29.974
Abundance = 20.444%
Averages atomic mass
= (Mass of A x abundance of A)/100 + (Mass of B x abundance of B)/100 + (Mass of C x abundance of C)/100
= (27.977x78.21)/100 + (28.976x1.346)/100 + (29.974x20.444)/100
= 21.8808117 + 0.39001696 + 6.12788456
= 28.40
Creates one million jobs (500 000 direct and 500 000 indirect).
Accounts for about 18% of GDP (8.6% direct, 10% indirect and induced).
Is a critical earner of foreign exchange at more than 50%.Accounts for 20% of investment (12% direct).
Attracts significant foreign savings (R1.9-trillion or 43% of value of JSE).
Accounts for 13.2% of corporate tax receipts (R17-billion in 2010) and R6-billion in royalties.
Accounts for R441-billion in expenditures, R407-billion spent locally.
Accounts for R78-billion spent in wages and salaries.Accounts for 50% of volume of Transnet’s rail and ports.
Accounts for 94% of electricity generation via coal power plants.
Takes 15% of electricity demand.
About 37% of the country’s liquid fuels via coal.<span>
</span>With South Africa’s economy built on gold and diamond mining, the sector is an important foreign exchange earner, with gold accounting for more than one-third of exports. In 2009, the country’s diamond industry was the fourth largest in the world. South Africa is also a major producer of coal, manganese and chrome.
Answer:
The internal energy(ΔE) of a substance is calculated below:
From the first law of thermodynamics;
ΔE=q+w
Explanation:
<u>ΔE=q+w</u>
here;
+q=endothermic reaction
-q=exothermic reaction
+w=work done on the system
-w=work done by the system
Given:
q=+1.62kJ=1620J
w=-874J
To solve:
the internal energy(ΔE)
We know:
ΔE=q+w
<em>according to the problem;</em>
ΔE=q-w
since;
w=-874J (i.e.)work is done by the system.
ΔE=1620-874
ΔE=+746J
Therefore the internal energy is +746J
i.e. the option is "c"(+746J)
Answer:
c
Explanation:
The batter aint changing the force he is using while hitting Ball B. Therefore, Motion of ball b will stay the same :D