Let a, = 5 a2 a3 2 determine what value(s) of a will make {a,,a2,as} a linearly dependent set. 2. (1 point) let t: r^4 --> r^2 be a transformation such that t(x) = ax. what size must a have in order to define such a mapping? ( type sizes with the $\times$ command rather than using an "x").