**4. Incorrect.** **The answer is
false not true**. If we calculate the definite integral between 0 and 0.5,
then we will have that:

6 [1/2x ^{2 }|_{0}^{0.5}]
- 6 [ 1/3 x ^{3 }|_{0}^{0.5}] = 6[1/8 - 1/24] = 0.5.

So, the oil company will discover crude oil with a 50% of probability.