\[\begin {array} {1 1} (a)\;6 \bigg(\hat i- \hat j+\frac{1}{3} \hat k \bigg) & \quad (b)\;0.6 \bigg(\hat i-\hat j+\frac{1}{3} \hat k\bigg) \\ (c)\;6 \bigg(\hat i+\hat j+\frac{1}{3} \hat k\bigg) & \quad (d)\;0.6 \bigg(\hat i+\hat j-\frac{1}{3} \hat k\bigg) \end {array}\]