The most common unit is meters (m for short). It is the base unit for distance or displacement in the metric system. If you are dealing with larger distances, you might use kilometers (I'm for short) which is just 1000 meters. On the other hand, centimeter (cm) are used for small distances and are 1/100 of a meter. Another common unit is millimeters (mm) which is 1/1000 of a meter.
Their relative speed is the sum of 60 and 40 or 100km/hr. They will travel the 150km in 1.5 hrs. When two object approach each other, the closing speed is just the sum of the speeds, therefore, the closing speed is your case is 100kph. So they will meet in 1.5 hours.
Answer:
A) how your body uses oxygen
The primary colors of light are red, blue and green.
There are the pigments like yellow, magenta and cyan that are the mixture of two primary colors.
For example, magenta is a mixture of red and blue color. Thus, it reflects the red and blue color. Also, magneta absorbs the green color.
These type of colors that reflects two primary colors and absorb one color are known as secondary pigments.
Hence, 2nd option is the correct answer.