The answer is a.12.5kg because i just did the test and it was correct.
hope this helps
Base on my research, as of 2004 The U.S. devours about 20 million barrels of oil a day, according to the CIA. But base on Wikipedia, it says that a normal large tanker can only carry around 2 million barrels of oil. So to supply the U.S with this oil per day, it needs 10 normal large oil tankers.
That ratio is called"efficiency". It doesn't need to be a percent.
It can just as well be a fraction or a decimal number.
The angle of inclination is calculated using sin
function,
sin θ = 5 m / 20 m = 0.25
θ = 14.4775°
<span>The net force exerted is then calculated:
F net = m g sin θ = 20 * 9.8 * 0.25 </span>
F net = 49N
<span>Work is product of net force and distance:
W = F net * d = 49 * 20 </span>
<span>Work = 980 J </span>
I think it is D. I hope this helps