let g be a connected reductive group with maximal torus t, and let v and e be two representations of g. then e defines a vector bundle on the orbifold v//g; let x//g be the zero locus of a regular section. the quasimap i-function of x//g encodes the geometry of maps from $p^1$ to x//g and is related to gromov-witten invariants of x//g. by directly analyzing these maps from $p^1$, we explain how to relate the i-function of x//g to that of v//t. our formulas prove a mirror symmetry conjecture of oneto-petracci that relates the quantum period of x//g to a certain laurent polynomial defined by a fano polytope. finally, we describe a large class of examples to which our formulas apply, examples that are the orbifold analog of quiver flag varieties. question for the audience: what else can one investigate with these examples?