Answer: Time taken by a sound impulse to travel through an aluminum rod 25 kilometers long is 4.9 seconds.
Solution:
Length of aluminium rod = 25 km = 25000 m (1 km=1000 m)
Time taken by sound to travel through aluminium = 5100 m/s (from the table given)

time taken =
Hence, the correct option is 4.9 seconds.
Answer:
5.6 L
Explanation:
We can apply Charles' Law here since our pressure is constant (will not change inside the refrigerator) and we are relating change in volume with change in temperature:
V₁ / T₁ = V₂ / T₂ where V₁ and T₁ are initial volume and temperature, and V₂ and T₂ are final volume and temperature. Let's plug in what we know and solve for the unknown:
28.0 L / 25 °C = V₂ / 5 °C => V₂ = 5.6 L
5.6 L is our new volume (at 5 °C).
Divide mass by the volume to find density.
The first one would be it
<u>Answer:</u>
<em>Silver tarnishing as the silver metal reacts with sulphur is a chemical change.</em>
<u>Explanation:</u>
Tarnishing is the process of chemical change occurring on the surface of objects leading to corrosion or other defects on the surface. The remaining options like dilution, eroding is a physical change where the concentration of salt and rock particles will be decreased, respectively.
Similarly for soil drying also the concentration of water will be decreased leading to a physical change from wetty or dry soil.
But the last option which indicates tarnishing of silver metal on reaction with sulphur is a chemical process as the surface of silver metal will be reacting to sulphur and leads to lose of electrons which leads to corrosion of the surface or tarnishing of silver.