what proportion of elected officials in the united states represents single member districts? A all officials at the federal level: none at state and local levels B across local, state, and federal levels C All officals at each level of government D None

For 50 pointsfredrika's science teacher asked her to bring in three abiotic items from her backyard ecosystem. which of the following groups of items should she bring? a. a lightning bug, a plug of grass, and a wormb. a smooth rock, some red dirt, and an empty bird's nestc. a ladybug, a spider, and some water from a mud puddled. a caterpillar, a pine cone, and a piece of a robin's egg

Dr. redbull conducts a study to determine whether her new energy drink children perform better on spelling tests. she randomly assigns children to one of two groups: group 1 receives her energy drink and group 2 receives water. she then gives both groups a spelling test and compares the results. which of the following is true about this study? a. group 1 is the dependent variable and group 2 is the independent variable. b. this is a correlational study. c. group 2 is the experimental group. d. the independent variable is the type of drink the children receive.

Pj conducts an experimental study on the effects of soft music during high stakes science testing. he randomly assigns students at the school. in one condition he does not provide music for testing while in the other group he does provide the music. he administers a pretest at the beginning of the year and a posttest at the end of the year. pj’s design is best described as a: a.static group comparisonb. pretest-posttest control group designc.control-group-time-series designd. nonrandomized control-group pretest-posttest design