一道英语的高中数学题,回答用中文就可以,
Thediagramshowsthegraphofaquadraticfunction(抱歉没有图).Thegraphpassesthroughthepoints(6,0)and(p,0).Themaxinumpointhascoordinates(0.5,30.25).
(a)Calculatethevalueofp.
(b)Giventhatthequadraticfunctionhasanequationy=-x^2+bx+c,findbandc.