P=50-Q/10 ,total Cost Ofspring Water Are Given By. C(Q)=0.05Q2+2000. find output level(Q)of profit maximization.

I assume P(Q) is the price. So, the revenue

R(Q) = Q*P(Q)

profit is thus

R(Q)-C(Q) = Q(50-Q/10)-(0.05Q^2+2000)
= -0.15Q^2 + 50Q - 2000

now just find the vertex of the parabola.