6. Rajan wants to check if light can pass through water to which a few drops of black ink have been added. Which of the following
MUST he do to find this?
A. use water that is cold
B. b

The correct options for the given question are given below:

a. use water that is cold

b.boil the water before use

c. take the water in a clear cup

d. measure the exact amount of water used

The correct answer is - C. take the water in a clear cup.

Explanation:

In order to check that if light can pass through the water to which a few drops of black ink have been added Rajan needs to have water in a clear cup or container and put some drops of black ink added to it and place the cup in the light.

There must be a clear cup so it can be observed if the light passes through the ink and reach below the surface covered with the ink as ink spread over the water surface due to surface tension of the water and difference in the density. So to check the light passes or not it requires a clear or transparent cup.

c. earths continental crust is thicker than its lithosphere.

because, the lithosphere is the outermost layer of the earth/ 100 km thick and is defined by its machanical properties.the lithosphere contains oceanic and continental crust that varies in age and thickness across locations and geologic time. the lithosphere is the coolest layer of the earth in terms of temperature. the term lithosphere should not be confused with the use of "geosphere" which is used to indicate all of earth systems, including the atmosphere, hydrosphere   and biosphere. the surface of the earth can be divided into the continental crust and the oceanic crust.   the continental crust is made mostly of granite while the oceanic crust is made of basalt. the average thickness of the continental crust is 25 miles and the average thickness of the oceanic crust is 5 miles.   three types of rock, igneous, sedimentary, and metamorphic, make up the surface of the earth. that's why 3 option is preferable.