Answer:
After the assassination of Luis Carlos Galán, the administration of César Gaviria moved against Escobar and the drug cartels. ... Declaring an end to a series of previous violent acts meant to pressure authorities and public opinion, Escobar surrendered to Colombian authorities in 1991.
Roberto Escobar maintains Pablo fell into the drug business simply because other types of contraband became too dangerous to traffic. As there were no drug cartels then, and only a few drug barons, Pablo saw it as untapped territory he wished to make his own.
Explanation:(a) Was this an observational study or an experiment? Explain your reasoning. Experiment, because certain variables were controlled (he sets the screen brightness to low and then starts a movie) to determine if iPhones last longer if the screen brightness is set to low, and it proves the cause and effect relationship.
(b) What is the explanatory variable and the response variable? Response Variable- To determine if iPhones last longer if the screen brightness is set to low Explanatory variable- he sets the screen brightness of 10 of the iPhones to high and starts a movie, then the other 10 to low and starts a movie.
(c) Was a random sample used to collect the data? Yes- “he selects a random sample of 20 brand new iPhones”
Answer:
a plant cell has a cell wall and animal cells do not
Explanation: