Black lung disease was a common illness among coal miners in the 1950s, but it is almost unheard of in miners today. a. true b. false

a- all cells come from pre-existing cells

answer: although many types of viruses can cause a common cold, rhinoviruses are the most common culprit. a cold virus enters your body through your mouth, eyes or nose. the virus can spread through droplets in the air when someone who is sick coughs, sneezes or talks. theres your answer

explanation:

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.

i know can you plzz me with this question im sorry i didt answer your question i just need hel.