Answer:
The number of freely-moving neutrons decreases over time.
The number of freely-moving neutrons decreases over time.
Explanation:
C. Both A. and B.
Explanation:
Statement A. Reducing the volume is true because of Boyle's law, which states that for a gas at fixed temperature, the pressure p and the volume V are inversely proportional:

Therefore, when the volume V is reduced, the pressure p increases.
Statement B. Adding more gas is also true: in fact, if we add gas into the container, we will have more molecules of the gas hitting the wall of the container. But the pressure of a gas is exactly given by this: by the collision of the molecules against the wall of the container, so the more the molecules of gas, the greater the pressure.
Answer:
<u>The asteroid was not detected until it was extremely close to Earth. </u>
Explanation:
According to data from NASA, the Asteroid named 'Astriod 2019 OK', was detected when it was extremely close to earth with just about an estimated distance of 73,000 kilometers (45,000 miles) from the Earth.
Scientists were concerned at the proximity of this space object to the Earth before it was discovered, and it brought about a cause of concern that since it was not extremely large (estimated 57 to 130 meters wide) it creates a potential for other smaller asteroids to escape detection and struck the earth.
Given: The number = 0.0069 that has to be expressed in scientific notation
Concept: When we express any number in scientific notation then we shall consider two points.
(i) If we shift the decimal point from left to right after first (non-zero) digit then we count the number of shifted place of decimal and write them in terms of the negative power of 10. For example, 0.004789 = 4.789 ×10⁻³
(ii) If we shift the decimal point from right to left after first (non-zero) digit from the left end then we count the number of shifted place and write then in terms of the positive power of 10. For example, 4789.24 = 4.78924 ×10⁺³ = 4.78924 ×10³ Now, we shall convert the given number 0.0069 in scientific notation
0.0069 = 6.9 ×10⁻³ because we have shifted the decimal from left to right for three places that is after digit 6.
Hence, the last option 6.9 ×10⁻³ will be the correct option.
Answer:
The specific heat of aluminum is greater.
Explanation:
It lost the most heat.