Explanation:

- Statement 1: Dot product over vector addition is distributive.

- This is true: $(\mathbf{a}+\mathbf{b})\cdot \mathbf{c}=\mathbf{a}\cdot \mathbf{c}+\mathbf{b}\cdot \mathbf{c}$.

- Statement 2: Cross product over vector addition is distributive.

- This is also true: $(\mathbf{a}+\mathbf{b})\times \mathbf{c}=\mathbf{a}\times \mathbf{c}+\mathbf{b}\times \mathbf{c}$.

- Statement 3: Cross product of vectors is associative.

- This is false: $(\mathbf{a}\times \mathbf{b})\times \mathbf{c}\ne \mathbf{a}\times (\mathbf{b}\times \mathbf{c})$.

- Option 3: 1 and 2 only.

- This option is correct as both statements 1 and 2 are true.