Get the Algebraic Ecpression In The Following
(i) Subtraction of z from Y.
(ii) One Half of The Sum Of Numbers X and Y.
(iii) The NUMBER multiplied Itself
Answers
Answer:
What are the three layers of the earth?
Answer: the three layers of earth are :
Crust
Mantle
Core
(ii) What is a rock?
Answer: Any natural mass of mineral matter that makes up the earth’s crust is called a rock. The earth’s crust is made up of various types of rocks of different texture, size and colour.
(iii) Name three types of rocks.
Answer: the three types of rocks are:
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks
(iv) How are extrusive and intrusive rocks formed?
Answer: The molten lava comes out of volcanoes, reaches the earth’s surface and cools down rapidly to become a solid piece of rock. This is how extrusive rocks are formed. For example – basalt.
When the molten lava solidifies deep inside the earth’s crust, the rocks so formed are called intrusive rocks. For example – granite.
(v) What do you mean by a rock cycle?
Answer: The process of transformation of rocks from one type to another, due to changes in certain conditions in a cyclic manner, is called a rock cycle.
(vi) What are the uses of rocks?
Answer: Rocks are useful for various purposes:
It helps in making roads
It is used in the construction of houses and buildings
Small stones are used by children in different types of games
They are used in fertilisers
(vii) What are metamorphic rocks?
Answer: The type of rocks formed when igneous and sedimentary rocks experience heat and pressure are called metamorphic rocks.