input: OPTIONS:
- desert patina
- desert shadow
- desert rust
- desert varnish Now, answer this question: Answer the following question given this paragraph: Exposed rocks in desert areas often develop a dark brown or black coating called desert varnish ( Figure below ). Wind transports clay-sized particles that chemically react with other substances at high temperatures. The coating is formed of iron and manganese oxides. Q: What is the term for the dark brown or black coating found on exposed desert rocks, which is formed of iron and manganese oxides? A:
A:
output: desert varnish

Answer the following question given this paragraph: Earth is just a tiny speck in the Universe. Our planet is surrounded by lots of space. Light travels across empty space. Light is the visible part of the electromagnetic spectrum . Astronomers use the light and other energy that comes to us to gather information about the Universe. Q: What is the term for the visible part of the electromagnetic spectrum? A:

OPTIONS:
- chroma
- gravity
- electricity
- light

Answer: light

Problem: OPTIONS:
- weight
- height
- size
- time
Q: Answer the following question given this paragraph: Calculating acceleration is complicated if both speed and direction are changing. It's easier to calculate acceleration when only speed is changing. To calculate acceleration without a change in direction, you just divide the change in velocity (represented by ) by the change in time (represented by ). The formula for acceleration in this case is:. Q: To calculate acceleration without a change in direction, you just divide the change in velocity by the change in what? A:
Answer: time

Problem:OPTIONS:
- volume
- length
- weight
- density

Answer the following question given this paragraph: Calculations are described showing conversions between molar mass and density for gases. Q: Calculations are described showing conversions between molar mass and what for gases? A:
****
A: density

Answer the following question given this paragraph: The continent of Antarctica is covered with an ice cap. Q: Which continent is covered with an ice cap? A:
OPTIONS:
- asia
- greenland
- australia
- antarctica
antarctica

Answer the following question given this paragraph: Saturated hydrocarbons contain only single bonds between carbon atoms. They are also called alkanes. They may form straight-chain, branched-chain, or cyclic molecules. Compounds with the same number of atoms but different shapes are called isomers. Q: What is another word for saturated hydrocarbons? A:
OPTIONS:
- catalysts
- enzymes
- aldehydes
- alkanes

Answer:
alkanes