A scientist wants to find the percent of teens that like the taste of "brand X" lemonade over "brand Y" lemonade. She conducts a taste test of 500 teenagers. She gives each teen a bottle of lemonade with the labels showing the brand of each lemonade. She asks each teenager to taste each brand after drinking water in between. She finds that 50% of teens like brand X and 50% like brand Y lemonade. Why are the results of the survey most likely unreliable? Adults were not interviewed.

Not enough teens were interviewed.

The investigation was based on taste.

The lemonade labels introduced bias.

your spelling is a little off : ]

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.

straight probes are used primarily for measuring flow as it is approaching the test area. its geometry allows the probe to be mounted so that it is in the direct line of airflow.