Asound wave travels through air. in which regions are air molecules the least dense?

Transfer chemicals from one location to another to weather objects. a-water b-physical weathering c-chemical weathering

Which statement is true if the refractive index of medium a is greater than that of medium b? a. total internal reflection is possible when light travels from air to medium b to medium a. b. total internal reflection is possible when light travels from medium a to medium b. c. total internal reflection is possible when light travels from medium b to medium a. d. total internal reflection is possible when light travels from air to medium a. e. total internal reflection is possible when light travels from air to medium b.

Consider a production line with five stations. station 1 can produce a unit in 9 minutes. station 2 can produce a unit in 10 minutes. station 3 has two identical machines, each of which can process a unit in 12 minutes (each unit only needs to be processed on one of the two machines. station 4 can produce a unit in 5 minutes. station 5 can produce a unit in 8 minutes. which station is the bottleneck station?