Answer in complete sentences.
1. how do we know that the earth is approximately spherical? what is the earth’s true shape?
2. describe the effects of earth’s rotation on its axis.
3. briefly describe the positive and negative aspects of the map projections listed below.
mercator projection:
goode projection:
polar projection:
4. explain the global timekeeping system. mention standard time, standard meridians, and time zones in your answer.

Answers given below.

Explanation:

Earth is not a perfect sphere but a geoid or elliptical, some claim that distance of the sun and rapid spinning of the earth on its axis from the equator to the poles is narrowed downwards. Effects of this rotational motion influence the seasons and oceanic currents and wind patterns. The angle of inclination that the sun makes with the earth is also affected due to the tilt and hence there is uneven heating of the earth at various altitudes. As the aspect of positive map projection is that it helps in navigation such as that of the Mercators projection but it distorts the upper spheres of earth and the Googe projection is an equal-area projection used in multiple worldwide interruptions also called as homolographic projection. Guillaume Postel created the polar projection used it represents the north polar regions. Its drawbacks are that the southern hemispheres of the map are distorted heavily. The time zones for the northern hemisphere and southern hemispheres are divided from the UTC points in Greenwich England.  

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen