Latitude lines run horizontally and indicate the north-south position of a location. This measurement is essential for understanding how far a place is from the Equator.

The Equator is the reference line for 0° latitude that divides the Earth into the Northern and Southern Hemispheres. It is a fundamental component of the geographic coordinate system.

Longitude lines, or meridians, measure the east-west position relative to the Prime Meridian. This measurement is critical for pinpointing exact locations on a map.

The Prime Meridian is defined as 0° longitude and passes through Greenwich, England. It serves as the baseline for measuring distances east and west around the globe.

Longitude lines extend from the North Pole to the South Pole, making them run in a north-south direction on most map projections. This orientation helps delineate time zones and geographic positions.

A positive latitude (N) indicates the Northern Hemisphere, while a positive longitude (E) signifies the Eastern Hemisphere. Hence, 45° N, 90° E is the correct representation.

The Equator is the fundamental line at 0° latitude that evenly splits the Earth into the Northern and Southern Hemispheres. This line is essential for understanding global geographic balance.

The Earth is divided such that every 15° of longitude approximately corresponds to a one-hour difference in local time. This system allows for standardization of time globally.

In geographic coordinates, negative latitude values signify locations south of the Equator. This standard helps differentiate between the two hemispheres.

Latitude lines are parallel, meaning the distance between them remains constant. Conversely, longitude lines converge as they approach the poles, reflecting the Earth's spherical shape.

A coordinate with a negative latitude (S) indicates the Southern Hemisphere, and a negative longitude (W) indicates the Western Hemisphere. Thus, 30° S, 60° W correctly places the location.

One degree of latitude is roughly equivalent to 69 miles or 111 kilometers on Earth. This approximation is commonly used to estimate distances between latitudinal points.

Longitude lines converge as they approach the poles, which means the physical distance between them decreases at higher latitudes. This effect is a direct consequence of projecting Earth's spherical surface onto a two-dimensional map.

The North Pole is defined by a latitude of 90° N. Although longitude is technically undefined at the poles because all meridians converge there, it is commonly simplified as 0° for basic mapping purposes.

The Tropic of Cancer and Tropic of Capricorn lie at about 23.5° north and south of the Equator, respectively. These lines mark the limits of the tropics and are important for understanding climatic zones.

The International Date Line is approximately positioned at 180° longitude, directly opposite the Prime Meridian at 0°. This separation is key in understanding the global system of time zones and navigation.

A coordinate of 60° N places the location well above the United States, into the higher latitudes typically associated with Canada. The longitude of 100° W further reinforces its placement in northern regions of North America.

While latitude is a major determinant of climate, local factors such as ocean currents, altitude, and prevailing winds can cause significant climate variations even along the same latitude. Therefore, sharing a latitude does not guarantee identical climatic conditions.

The Equator is defined by 0° latitude, so coordinates with latitudinal values very close to 0° are nearest to it. A reading of 0.5° N is much closer than the other options provided.

The Mercator projection is known for distorting distances and areas, particularly as one moves towards the poles. This exaggeration is a result of the mathematical method used to project a spherical surface onto a flat map.