Achange in matter that produces one or more new substances is a(n)

According to the vsepr theory what is the shape of a molecule that has a central atom valence three other items with no lone pairs of electrons

How have the greenhouse gasses increased from the year 2000 to 2018

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space