Well it occurs in igneous, metamorphic, and sedimentary rocks.
quartz is a mineral, not a rock.
it is abundant or in other words rich.
Answer:
300 m
Explanation:
The train accelerate from the rest so u = 0 m/sec
Final speed that is v = 80 m/sec
Time t = 30 sec
The distance traveled by first plane = 1200 m
We know the equation of motion 
where s is distance a is acceleration and u is initial velocity
Using this equation for first plane 
As the acceleration is same for both the plane so a for second plane will be 2.67 
The another equation of motion is 
using this equation for second plane 
s = 300 m
The force required to start an object sliding across a uniform horizontal surface is larger than the force required to keep the object sliding at a constant velocity once it starts.
The magnitudes of the required forces are different in these situations because the force of kinetic friction is less than the force of static friction. <em>(d)</em>
<span>1.0 gram (g) of electrons would contain 10^27 electrons
Electrons have an electric charge of −1.602×10−19 coulomb
so total charge of 1 g electrons = -1.602 x 10^-19 x 10^27 = -1.602 x 10^8</span>
