Experiments in environmental toxicology can sometimes be manipulative experiments in which the researcher actively chooses and manipulates the independent variable. in hunt's study, for example, dosages of bpa were manipulated and the effects were measured. in manipulative studies, the researcher controls all the other variables in the experiment, so any health effects observed in the test subjects can be attributed to differences in the independent variable.

Acommittee that exists permanently in either the house of representatives or the senate is called a a. permanent committee b. long-term committee c. standing committee d. enduring committee select the best answer from the choices provided

What was one step that charlemagne took to unite his kingdom? a. he chose a single strong heir to inherit his throne. b. he drove muslim forces out of europe. c. he created and supported schools. d. he declared himself head of the catholic church.

Choose the best example of an indirect confrontation for the following situation: peter, a local school board member hired john whom owns a local print shop to make custom t-shirts for his son's basketball team, the ravens. they are about to play their final game of the year and are having a party to celebrate their semi-finalist rankings. unfortunately, the printer made a mistake and printed on red/blue shirts instead of black/blue which are the team's actual colors. peter explains to john that the team's colors are black/blue instead of red/blue and asks john what he thinks they should do. peter explains to john that the team's colors are black/blue and demands that john re-print the shirts on the correct colors. peter agrees to take the red/blue shirts but then posts a negative yelp review on john's business. peter agrees to take the red/blue shirts but tells everyone he can in the school about the incident and tells them not to buy from john. peter rejects the shirts and files a lawsuit to attempt to recover the down payment he made to john.