With gupta advancements in mathmatics and astronomy, which of the following discoveries were most important to future generations? mark all that apply. use of zero as a placeholder numeric decimal system observing the earth to be round due to shadows concluding the earth spins on an axis use of coins as money

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