<span>The relative hardness of a mineral
can be tested by the Moh’s scale or the mineral hardness. The Moh’s scale can
be characterized by the ability of the mineral to resist scratch resistance by
scratching a harder or softer mineral. It has a scale of 1 to 10 where 1 being
the softest and 10 being the hardest. The relative hardness of a mineral can
best be tested by scratching the mineral across a glass plate. The answer is
letter A. </span>
Answer:

Explanation:
When wings of the airplane makes an angle of 40 degree with the horizontal so here we can say that force due to air is having two components


now we know that


also we know that


now plug in all data in above equations




Answer:
d
Explanation:
Ya gon find the Kenitic Energy first
K=½mv²===> K=½×0.2×(0.2)²===> 0.1(0.04)===> 0.004
and now the replacement:
0.004=½×0.4V²====> v²=0.02===> V=0.14m/s
Type of conductors determines rate of flow of current
Escape velocity is the speed that an object needs to be traveling to break free of a planet or moon's gravity well and leave it without further propulsion. For example, a spacecraft leaving the surface of Earth needs to be going 7 miles per second, or nearly 25,000 miles per hour to leave without falling back to the surface or falling into orbit.