Which of the following is the best way to determine if a substance is an element? (melting point, boiling point, what it is made of, density)

Juan created a chart to him study for a test. which headings best complete the chart? x: transparent objects y: opaque objects x: opaque objects y: transparent objects x: high frequency waves y: low frequency waves x: low frequency waves y: high frequency waves

Why should seat belts not be mandatory quick plz

Acold front traveling southeast collided with a warm front traveling northwest the following map shows the weather on monday the day the two fronts collided which of these describes the weather forecast for mississippi on tuesday and wednesday