What must be known to find an object's average speed? *direction and time
*distance and time
*displacement and direction

distance and time

Explanation:

total distance/ total time

Five words that contain the Greek/Latin root/affix calc- are:

1) Calcification

2) Calcined

3) Calcium

4) Calcinosis

5) Calcite

Explanation: A root word is a word or morpheme to which a prefix and/or a suffix gets attached in order to form new words. In that way, the same root can appear in different words. One example is the root word "calc-", which comes from Greek and Latin and means "stone". "Calc-" appears in many words: some of them are "calcification", "calcined", "calcium", "calcinosis" and "calcite". All of them have a meaning related to the one of the root, that is to say "stone"; however, they have different denotations as they are made up of different suffixes.