Answer: Option [C]The correct answer is India and Saudi Arabia. The Tropic of Cancer passes through 16 countries: Algeria, Niger, Libya, Egypt, Saudi Arabia, United Arab Emirates, Oman, India, Bangladesh, Myanmar, China, Taiwan, Mexico, Bahamas, Mauritania and Mali.
Answer: Option [D]The correct answer is both iron and magnesium in the plastic state. The innermost part of the earth is called core. It is mainly made up of iron and nickel. Unlike the mineral-rich crust and mantle, the core is made almost entirely of metal—specifically, iron and nickel. The shorthand used for the core's iron-nickel alloys is simply the elements' chemical symbols—NiFe. Elements that dissolve in iron, called siderophiles, are also found in the core.
Answer: Option [B]The correct answer is Silica. Silica, also called silicon dioxide, compound of the two most abundant elements in Earth's crust, silicon and oxygen, SiO2. The mass of Earth's crust is 59% silica, the main constituent of more than 95% of the known rocks.
Answer: Option [A]The correct answer is Oxygen. Oxygen is by far the most abundant element in the Earth's crust, making up 46% of mass—coming up just short of half of the total.
Answer: Option [D]The approximate circumference of the Earth is 40075 km. The equatorial circumference of the equator is 40075 km. The equator is known as the great circle of the earth and it is situated at zero degree latitude. However, from pole to pole — the meridional circumference — Earth is only 24,860 miles (40,008 km) around. Our planet's shape, caused by the flattening at the poles, is called an oblate spheroid.