QUIC I WILL GIVE BRAINLIEST Scientists have discovered a new pathogen named Virus X. This infection causes its victims to suffer from severe diarrhea and is spreading quickly across major cities around the world. During their investigation, these researchers tracked the virus back to a population of pigs in Asia. These animals were not affected by the disease themselves but large numbers of the virus were found in their feces. In particular, when visiting one farm, scientists observed workers routinely going from taking care of the pigs to picking fruits and vegetables without washing their hands. The Virus X outbreak would best be described as...

an epidemic.

endemic.

a pandemic.

sporadic.

On a backpacking trip, kenny hikes all day at a steady pace, covering 30 kilometers and burning 4000 calories. at the school track, janelle runs the 100-meter sprint in 13.5 seconds, burning 10 calories. afterward, janelle’s leg muscles are aching and she is breathing hard, while kenny maintains normal breathing all day, even though he burns 400 times more calories than janelle. which two statements offer the best explanation for this phenomenon? a. if the aerobic pathway—cellular respiration—cannot meet the energy demand, then the anaerobic pathway—lactic acid fermentation—starts up, resulting in lactic acid buildup and "oxygen debt." b. aerobic cellular respiration produces more energy, but its use is limited because of lactic acid buildup in the muscles and the resulting "oxygen debt." c. after about 90 seconds of intense exercise, the muscles become depleted of oxygen, and anaerobic respiration can no longer function to produce atp, resulting in "oxygen debt." d. the rate of energy demand determines how the muscles will obtain energy, either from cellular respiration or from lactic acid fermentation if not enough oxygen is present.