If a→ is a vector and m is a scalar such that m.a→=0 then what are the alternatives for m and a→ ?

If $\vec{a}$ is a vector and m is a scalar such that m. $\vec{a}$ =0 then what are the alternatives for m and $\vec{a}$ ?

Matching exercise

Match the items on the right to the items on the left.

Step1

Step2

Step3

Step4