The correct answer is C. more mass and less distance between two objects.
Answer:
a) 2.22 %
b) Range would be 60±1.998 km/h
Explanation:
Percentage uncertainty indicates the error of a reading. With the percentage uncertainty error for a measurement can be calculated.
a) Percentage uncertainty would be

Percent uncertainty is 2.22%
b) For 60 km/h error would be

Range would be 60±1.998 km/h
Burning of gases is one the example of chemical change
Answer:
C)Earth's orbital speed is greater when it is closer to the Sun than when it is farther from the Sun.
Explanation:
We can use Kepler's 2nd law or the law of area to answer this question.
The law states that the rate of area swept out by a planet's orbit is same throughout the orbit. For the farthest point since the distance is large as compared to to the nearest point, the possibility that area swept is large. Hence, to compensate the extra swept area. the orbital speed has to decrease at the largest point.
Hence, planet's speed is greater when it is closer to sun than the speed when it is farther.