Which of the following is a part of a wave?

a. crest
c. trough
b. drift
d. both a and c

Two rigid transformations are used to map δhjk to δlmn. the first is a translation of vertex h to vertex l. what is the second transformation? a reflection across the line containing hk a rotation about point h a reflection across the line containing hj a rotation about point k

Lightning is an example of what phenomenon? a release of a large amount of energy an absorption of a large amount of energy a natural electric circuit a natural electric current

Coal contains energy. a. light b. kinetic c. chemical d. mechanical