A car travels for an hour at a speed of 20 km/r, the next two hours at a speed of 65 km/r and the final hour at a speed of 85 km/r. What is the average speed of the car for the entire trip

a high pressure system is a dense air mass that is usually cooler and drier than the surrounding air. a low pressure system is a less dense air mass that is usually wetter and warmer than the surrounding air.

in general, areas that experience high atmospheric pressure also experience fair weather. low pressure systems can cause the formation of clouds and storms. air usually flows from areas of high pressure to areas of low pressure..

answer: i'm not sure which is which for i get confused on it all the time but i can tell you that the answer lies with the convex and concave devices. i hope this you. have a good day and best of luck to you!

explanation:

i believe the answer would be:

d. violin, clarinet, french horn, and tuba