4a)solar system is the collection of eight planets and their moons in orbit round the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets
4bi) -Mercury is the innermost of the eight planets in our Solar System. It is the second densest major body in the solar system after Planet Earth and its density is slightly less than the density of Earth.
-It orbits the Sun once in about 88 Earth days.
-Its diameter is 4,878km at its equator, which is about two-fifths of Earth’s diameter
The composition of the Earth consists of the solid and liquid portion and the atmosphere or gaseous portion.
-The earth is spherical in shape
The diameter of the Earth at the equator is 12,756 km (7,926 miles), and its circumference or distance around the Earth at the equator is 40,075 km (24,901 miles).
Delta is a triangular tract of sediment deposited at the mouth of a river, typically where it diverges into several outlets.
-The presence of a large catchment, or drainage, basin (the area where all run-off water drains to the river). The top 30 river deltas all have catchment basins in excess of 1,000,000 sq km.
– They all are at the mouth of large river systems that carry large quantities of clastic sediments (soils or portions of rocks that have been moved by water from where they formed).
-They are not near geologically active coastlines. In order to have a large catchment basin, a very complex tributary system is necessary. These long, complex systems take a long time to develop, so they are very rarely situated on tectonically active coasts.
6c) -The river must have large load. This will be possible if there is active erosion in the upper and middle stages.
-There should not be extensive deposition in the middle stage e.g. presence of lake in between or high evaporation rate (first).
-The river’s load must be deposited faster than it can be removed by the action of currents and tides.
7a) i) PRECIPITATION
(ii) Effects of geography
(iii) Earth’s surface
(i) Climate changes involving temperature affects man. Warmer temperatures make conditions more conducive to growing crops, which allows farmers to produce the food necessary to feed people and livestock. Adverse weather conditions, such as heat waves, droughts, flood and extreme cold, have a negative effect on agriculture, which reduces the available food supply.
(ii) Climate changes such as heat waves and flood can seriously impact health. These changes can also produce unhealthy water and limit or even deplete a region’s food supply.
(iii) climate changes involving the planet’s atmosphere can negatively affect human health.