Question

Your _____ indicates that the relative humidity is very high. Rain probably _____ occur. anemometer; will anemometer; won't hygrometer; will hygrometer; won't

Answer 1

The answer is hygrometer, will.

Your hygrometer indicates that the relative humidity is very high. Rain probably will occur. 
Hygrometer is an instrument used for measuring the relative humidity in the atmosphere. If the relative humidity is very high, then it rain will probably occur and vice versa.
Anemometer is an instrument used for measuring wind speed, thus it cannot be the right answer.

Answer 2

For this assignment from earth science and earth’s weather and climate unit you have to complete the statements shown above.

Answer: Your Hygrometer indicates that the relative humidity is very high. Rain probably will occur.

I hope this helps, Regards.