Subtract: -7 - (-21)

question 61

Multiple Choice

Subtract: -7 - (-21)

• A) -15
• B) 28
• C) -28
• D) 14
• E) -29

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Definitions:

Impermeable Layers

Geological strata that do not allow the passage of water or fluids due to their tightly packed nature.

Permeable Rocks

Rocks that contain pores or cracks through which fluids such as water can easily pass.

Oil And Gas

Natural hydrocarbon resources extracted from the Earth, used as fuels and in the production of various chemicals and materials.

Hydrocarbon Chains

Molecules composed of hydrogen and carbon atoms arranged in a chain, fundamental to organic chemistry and fossil fuels.