Which of these statements is correct about a theory? (2 points)

Avoiding bias, increases reliability and is important to experimental data. A scientist is investigating the cause of contamination of well water at a specific location. Four residents of the location responded to questions asked by the scientist. The chart below shows their responses. Questions Resident 1’s answer Resident 2’s answer Resident 3’s answer Resident 4’s answer Do you work at the gas station near the well? No Yes No Yes Does anyone in your family work at the gas station? No No Yes Yes Have you observed any change in the quality of well water? Yes No Yes Yes Which of these residents is most likely to provide reliable information? (2 points)

When a majority of scientists worldwide agree on a common explanation to a problem, the explanation is called a (2 points)

A scientific idea becomes valid when it is (2 points)

One group of students is investigating the properties of the bar magnet shown below. The students took a bowl of iron nails, plastic pieces, wood shavings, and paper pieces. The bar magnet was placed inside the bowl for some time and then taken out. Several iron nails were stuck on the bar magnet. The experiment was repeated by several students using different bar magnets. Based on the investigations, which of these theories would the students most likely propose? (2 points)

The diagram below shows two models of the atom. The models can be best used to (2 points)

A scientist plans to find out the percent of teenagers who like science. She interviews 500 teenagers leaving a science museum and finds that 450 of them like science. The scientist concludes that 90 percent of teenagers like science. Why is the scientist’s conclusion most likely unreliable? (2 points)

Which of these is a part of the geosphere? (2 points)

Which of these questions can be answered through science? (2 points)

One student burned a piece of paper weighing 4.8 grams. The table below shows the mass of the materials formed by burning the paper. Material formed Mass of material (in grams) Ash ? Smoke 2.2 Dust 2.5 What is most likely the mass of the ash formed on burning the piece of paper? (2 points)