Which type of force does a window washer want acting on him when trying to keep the same position

When you mate two plants together the terms is called? answer it fast as possible plz! i have a test tomorrow!

What forms when chemical reactions combine pollution with sunlight?

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 ?