Is the Godhead three persons or one?

The word “Godhead” is used only three times in the Bible, but does not disclose how many persons there are:

Acts 17:29 King James Version (KJV)
29 Forasmuch then as we are the offspring of God, we ought not to think that the Godhead is like unto gold, or silver, or stone, graven by art and man’s device.

Romans 1:20 King James Version (KJV)
20 For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse:

Colossians 2:9 King James Version (KJV)
9 For in him dwelleth all the fulness of the Godhead bodily.

The Bible says there are “three that bear record in heaven”, the “Father”, the “Word” and the “Holy Ghost”, and “these three are one”:

1 John 5:7 King James Version (KJV)
7 For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.

Jesus instructed his disciples to baptize in the name of the “Father”, the “Son” and the “Holy Ghost”:

Matthew 28:19 King James Version (KJV)
19 Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: