Help out this a quick one

Which uses electromagnetic radiation to discover the properties and composition of bodies in space? space probe space station space shuttle space observatory

Describe the difference between a. a hypothesis and a theory and b. an observation and an experiment.

3. how much energy in joules is required to evaporate .0005 kg of liquid ammonia to vapor at the same temperature? 4. how much energy ( in megajoules ) is given up by .75 kg of water at 0c when it freezes to form ice at 0c? 5. explain how heat works between and at critical temperatures?