Answer:
Explanation:
The cross product of two vectors is given by
Where, θ be the angle between the two vectors and \widehat{n} be the unit vector along the direction of cross product of two vectors.
Here, K x i = - j
As K is the unit vector along Z axis, i is the unit vector along X axis and j be the unit vector along axis.
The direction of cross product of two vectors is given by the right hand palm rule.
So, k x i = j
j x i = - k
- j x k = - i
i x i = 0
Radar waves are the waves with the lowest energy.
Answer:
over harvesting, pollution, introduction of invasive species such as new predators and food competitors
Explanation:
The main cause of mass extinction is Humans cause extinction of a species through overharvesting. The second main cause is pollution ., introduction of invasive species such as new predators and food competitors, habitat destruction, overhunting and other influences. Another very important cause of mass extinction is the unsustainable human population growth.
The five mass extinction events are
Ordovician Mass Extinction
Devonian Mass Extinction
Permian Mass Extinction
Triassic -Jurassic Mass Extinction
and Cretaceous -Tertiary (or the K-T) Mass Extinction.
Answer : 63 km/h
Explanation :
Outgoing distance = 300 km.
Outgoing speed = 93 km/h.
Break time = 1 h
Return distance = 300 km
Return speed = 56 km/h
Outgoing time = outgoing distance / outgoing speed
Outgoing time = 300 km / 93 km/h = 3.225806451612 h
Return time = return distance / return speed
Return time = 300 km / 56 km/h = 5.357142867142 h
Total distance =. Outgoing distance + return distance travelled
Total distance = 300 km + 300 km = 600 km
Total time = outgoing time + break time + return time
Total time = 3.225806451612 h + 1 h+ 5. 357142867142 h = 9.582949308754 h
Average speed = total distance / total time
Average speed = 600 km / 9.582949308754 h
Average speed = 62.61120462042 km/h = 63 km/h
