Instruments that orbit Earth's atmosphere and can show cloud cover, warm and cool regions, and invisible water vapor * 1 point
satellites
weather balloons
computer models
Doppler radar

What does polymerase chain reaction (pcr) do? o a. separates dna fragments by size o b. cuts a dna sample into fragments o c. provides an overall picture of a person's chromosomes o d. makes more copies of a sample of dna