The first S-wave of an earthquake took 4 minutes to travel to a seismic station from the epicenter of the earthquake. What is the seismic station’s distance to the epicenter of the earthquake and how long did it take for the first P-wave to travel that distance

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

the last one: artificial selection/genetic engineering

plant breeding is modifying the genetic composition of the plant - but this isn't cloning (which is specifically introducing a gene into a genome). but you are artificially selecting for the phenotype that you want.

the second one is literally genetic engineering - the gene would have been cloned first and then inserted or genetically engineered into the new plant cell (the cotton).