The food moves from the esophagus to the stomach by muscular contractions and relaxations. what do we call these contractions and relaxations?

his week a heat wave will be hitting, and most of the country will be experiencing temperatures above average for july. due to humidity, the temperature outside can feel even warmer than it actually is. this adjusted temperature, often referred to as the “feels like” temperature is called the heat index. the chart shows the heat index, which is calculated based on temperature and relative humidity. use this chart to answer the following questions.  

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