Answer:
Green house effect and human activity.
Explanation:
-The green house effect: Some gases in the atmosphere trap the heat and doesn't allow it to scape making the Earth warmer.
-Human activity: The industrial activities have increased the carbon dioxic levels that have contributed to the higher temperatures. Also, deforestation, fluorinated gases and fertilisers containing nitrogen have contributed to climate change.
Answer:
(a) Mean yearly temperature = 10.58
(b) 
Explanation:
Given:
The attached chart
Solving (a): The mean yearly temperature.
This is calculated as:
Solving (b): The mean July temperature.
From the chart:
Answer:
crust lower mantle and upper mantle
Explanation:
Answer:
Hydrogen in the core of the star is converted to helium by nuclear fusion. When the hydrogen supply in the core begins to run out, and the star is no longer generating heat by fusion, the core becomes unstable and contracts.
Explanation:
Convection occurs in the Earth's mantle because it is the most efficient way for the Earth to cool or dispose of its deep-seated heat content. In general, heat can be transferred by conduction, radiation or convection.
