Six vectors, $$\overrightarrow a $$ through $$\overrightarrow f $$ have the magnitudes and directions indicated in the figure. Which of the following statements is true ?

A particle has initial velocity $$\left( {3\widehat i + 4\widehat j} \right)$$ and has acceleration $$\left( {0.4\widehat j + 0.3\widehat j} \right).$$ Its speed after 10 s is

A particle shows distance - time curve as given in this figure. The maximum instaneous velocity of the particle is around the point

$$\overrightarrow A $$ and $$\overrightarrow B $$ are two vectors and $$\theta $$ is the angle between them, if $$\left| {\overrightarrow A \times \overrightarrow B } \right| = \sqrt 3 \left( {\overrightarrow A .\overrightarrow B } \right),$$ the value of $$\theta $$ is