The boy’s foot causes the motion. His foot is the one that causes the ball to roll down the hill.
Non living and dead are the same thing
A "screen" or even just a set of parallel bars are highly reflective to electromagnetic waves as long as the open spaces are small compared to the wavelengths.
"Grid" dishes work fine ... with less weight and less wind resistance ... for frequencies below about 3 GHz. (Wavelengths of at least 10 cm.)
(I even worked on a microwave system in South America where huge grid dishes were used on a 90-mile link.)
For the first one, leaves is matter.
for the second one, ability to react
hope this helps
Explanation:
<h3>The beam balance is a device used</h3><h3> for the determination of the mass of </h3><h3>a body under gravitation. It consists </h3><h3>of a beam supported at the centre </h3><h3>by an agate knife edge resting on a</h3><h3> support moving inside a vertical </h3><h3>pillar. The beam carries a light</h3><h3>pointer which moves over a scale.</h3>
