Th correct answer is letter A. Echo sounding is very useful for depth profiles where SONAR is used to determine the depth of water through the transmission of sound pulses. It is calculated by checking the interval between the mission and the pulse that is recorded within the SONAR device.
Answer:
The K-T extinction event is the global mass extinction that has taken place about some 65 million years back due to the asteroidal impact. This mass extinction event has wiped almost 75% of the plants and animal species from the earth's surface. The dinosaurs were extinct and very animal species have survived and undergone evolution in due course of time.|
The Cenozoic era started after the K-T mass extinction event, i.e from about 65 million years to the present.
Thus, the Cenozoic era is also known as the age of mammals because mammal were more abundant and diverse then. Many flowering plants evolved during this time and the earth experienced global cooling.
