Radiant energy is necessary for the production of which of the following? (a) oil, (b) wind, (c) moving water, (d) all of these. i picked b. is this correct?

Which of the following electromagnetic waves can create ions?

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 ?

No copying 15 pts how does a free-body diagram tell you about the net force on an object?