If you are talking about evolution, the two types of evidence is
1. fossil evidence
2. molecular evidence
one is adapted to live in a hot and dry environment and one is adapted to live in a humid environment.
A star's brightness is determined by the distance away from earth.
Explanation:
In the given question, the graph has been shown representing the change in temperature on Earth between 1900 to 1990. The graph has been made by plotting temperature ( °F) on y-axis vs Year on the x-axis.
From the graph, it can be observed that the temperature on Earth has increased over the years but between 1970 to 1990 the temperature has increased from 56.9 °F to 58.1 °F approximately.
The reason for this increase in temperature could be accounted to the fact that the burning of fossil fuels like petrol, gas, coal and others increased over these years which increased the amount of carbon dioxide and other harmful gases in the atmosphere.
Due to the increase in these gas, the greenhouse effect was observed and the temperature of the Earth begins to rise at an alarming rate.
The correct answer is (a.) a mutation of the hemoglobin allowing better oxygen-carrying capacity. The mutation of the hemoglobin that allows a better oxygen-carrying capacity would be the most beneficial to an elephant and its descendants.