Luke continued his written account in Acts 1:1-8 (NET):

I wrote (ἐποιησάμην, a form of ποιέω) the former account, Theophilus, about all that Jesus began to do (ποιεῖν, another form of ποιέω) and teach (διδάσκειν, a form of διδάσκω) until the day he was taken up to heaven, after he had given orders by the Holy Spirit to the apostles he had chosen.  To the same apostles also, after his suffering (παθεῖν, a form of πάσχω), he presented himself alive with many convincing proofs.  He was seen by them over a forty-day period and spoke about matters concerning the kingdom of God.  While he was with them, he declared, “Do not leave Jerusalem, but wait there for what my Father promised (ἐπαγγελίαν, a form of ἐπαγγελία), which you heard about from me.  For John baptized with water, but you will be baptized with the Holy Spirit not many days from now.”

So when they had gathered together, they began to ask¹ him, “Lord, is this the time when you are restoring the kingdom to Israel?”  He told them, “You are not permitted to know (γνῶναι, a form of γινώσκω) the times or periods that the Father has set by his own authority (ἐξουσίᾳ).  But you will receive power (δύναμιν, a form of δύναμις) when the Holy Spirit has come upon you, and you will be my² witnesses (μάρτυρες, a form of μάρτυς) in Jerusalem, and in all Judea and Samaria, and to the farthest parts of the earth.”

Addendum: September 29, 2018
Tables of Acts 1:6 and 1:8 comparing the NET and KJV follow.