Most matter in the universe is revealed by (powerful telescopes/radiation), but dark matter is detected by the degree to which (solar wind/light) bends on its way to earth

Which of the following elements is a representative element? a. chromium (cr) b. aluminum (al) c. mercury (hg) d. silver (ag)

What is the standard unit of measure for acceleration?

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?