Which of the following describes the benefit of using control in this experiment?
A biology student wanted to determine if using fertilizer
would promote plant growth. One hundred plants were
randomly assigned to one of two groups: one that used
the fertilizer, and one that did not use a fertilizer. Each
plant was planted in the same amount of soil and given
the same amount of water and light.
O By controlling the amount of soil, water, and light in
the experiment, we eliminate the need to have a
control group.
O By controlling the amount of soil, water, and light that
may influence the response variable, we reduce
variability in the response variable.
By controlling the amount of soil, water, and light that
may influence the response variable, we eliminate
variability in the response variable.
By controlling the amount of soil, water, and light, the
differences observed in the response variable can be
attributed to those variables that were controlled.

Do you mind if you guys me with this question i’m on number 8

Design an er diagram for keeping track of information about votes taken in the u.s. house of representatives during the current two-year congressional session. the database needs to keep track of each u.s. state's name (e.g., texas', new york', california') and include the region of the state (whose domain is {northeast', midwest', southeast', southwest', west'}). each congress person in the house of representatives is described by his or her name, plus the district represented, the start date when the congressperson was first elected, and the political party to which he or she belongs (whose domain is {republican', democrat', 'independent', other'}). the database keeps track of each bill (i.e., proposed law), including the bill name, the date of vote on the bill, whether the bill passed or failed (whose domain is {yes', no'}), and the sponsor (the congressperson(s) who sponsored - that is, proposed - the bill). the database also keeps track of how each congressperson voted on each bill (domain of vote attribute is {yes', no', abstain', absent'}). additional information:

In a survey of 1015 adults, a polling agency asked, "when you retire, do you think you will have enough money to live comfortably or not. of the 1015 surveyed, 534 stated that they were worried about having enough money to live comfortably in retirement. construct a 90% confidence interval for the proportion of adults who are worried about having enough money to live comfortably in retirement.