Which statements best describe oceanic crust? select the two correct answers.

a. its formed at zones of volcanic activity on the ocean floor.
b. it is made of all types of rocks.
c. it contains silicate minerals high in iron and magnesium.
d. it is between 25 and 70 km thick.
e. its age ranges from very young to more than 4 billion years old.

Options (A & C)

Explanation:

The statements that describes the oceanic crust are it contains high mineral contents like magnesium and iron, it is formed at volcanic zones on sea floor.

The reason behind is that it occurs due to the movement of continental plates over the sea area  diverge at mid ocean ridges where magna rises up . The lava thus  formed is  made from basalt igneous rocks which are rich in iron and magnesium contents

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.