Evaluate the expression: ∫01x2dx+∑n=13n2\int_0^1 x^2 dx + \sum_{n=1}^3 n^2∫01x2dx+∑n=13n2.
14.333...14.333...14.333...
433\frac{43}{3}343
141414
423\frac{42}{3}342