Find sin θ if theta is the angle between the vectors \(\;\vec a = 3\hat j + 4\hat k\;and\;\vec b = 6\hat i + 8\hat k\)

• A. 1/2
• B. 1/12
• C. \(\frac {3\sqrt{41}}{25}\)
• D. \(\frac {3\sqrt{31}}{25}\)