Answer:
efficiency of solar panel is 18%
Explanation:
Energy received by the sunlight is given as

here we know the dimensions of the plate as


now we have


now the power received by the sun light is given as

now the output power due to solar panel is given as



now the efficiency is given as



The granite would be older. As millions of years go by, rocks are affected by weathering and erosion. These processes break down rocks and scatter them. Rocks are broken down into sediments, which mix with other layers, which could have been the reason how the layer of sandstone contains the small fragments of granite.
An insulator which is also called a 'dielectric'.
Answer:

Explanation:
Given that,
Mass of the object, m = 100 grams
Volume of the object, V = 20 cm³
We need to find the density of the object. We know that, density is equal to mass per unit volume. So,

So, the density of the object is equal to
.