What should you always include in a great summary?
(select all that apply)
a. investigation plan
b. possible errors
c. predictions
d. new questions

The investigation plan and new questions.

Explanation:

If you are summarizing your research, you must always include what you have done or plan to do, so the investigation plan is mandatory. In addition, a great summary would include new questions that rise from the results of the investigation. Possible errors are not an obligatory inclusion, and predictions aren't either because predicting cannot necessarily be done with the results.

c. magnitude and direction