Yes.
Any parabola is represented by an appropriate second degree polynomial, which means that to identify a particular parabola you have to choose three coefficients [tex] a,b,c, \in \mathbb{R} [/tex] to identify the polynomial
[tex] ax^2+bx+c [/tex]
In your case, the expression [tex] -0.00635x^2+4.0005x [/tex] comes from the choice [tex] a = -0.00635, b = 4.0005, c=0 [/tex], and so by all means its graph is a parabola.
