Dr$.$ Smith, a laboratory scientist, has recently discovered a harmless chemical lotion which seems to grow hair. He wishes to market his product $($Hair Potion #$9)$ to the balding public but must first prove to his investors that the product is effective.$$ There are at least $2$ other hair replacement products that claim success in growing hair.$$ He designs a randomized clinical trial stratifying his sample on gender, to examine hair growth $($measured in hairs grown$)$ using $3$ products. He wishes to prove to his investors that his product is more successful at growing hair than either of the other two existing products. Data for this question is in the worksheet hair.

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IncorrectQuestion $6$

$0/3$ pts

Was there a sampling strategy used in this study? If so$,$ what type?

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No sampling was used

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Quisi$-$experimental method

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Experimental method