If she's African-American/White, then she's actually probably closer to a quadroon and not a mulatto at all. Her African-American parent was probably already carrying ~35% white DNA. So she'd be 67.5% White and not 50B/50W as a proper Mulatto.
Plus, the other consideration is where in Africa the family actually came from. There's quite a significant diversity of IQ among African ethnic groups. Nigerians for example are significantly higher than other groups. Any time the MSM focusses in on an exemplary African it's almost always a Nigerian.
As far as environmental affect on IQ. There are a few things in your environment that can retard brain development, extremely poor nutrition and lead poisoning be two. Unfortunately, there's no way to improve IQ from it's genetic baseline. All the brain-training, and early intervention stuff shows (very minor) IQ improvement in the short-term, but the effects even out over the participants lives, so it's really just training them to do the tests better, not actually making them significantly smarter.
She got lucky.
If she's African-American/White, then she's actually probably closer to a quadroon and not a mulatto at all. Her African-American parent was probably already carrying ~35% white DNA. So she'd be 67.5% White and not 50B/50W as a proper Mulatto.
Plus, the other consideration is where in Africa the family actually came from. There's quite a significant diversity of IQ among African ethnic groups. Nigerians for example are significantly higher than other groups. Any time the MSM focusses in on an exemplary African it's almost always a Nigerian.
As far as environmental affect on IQ. There are a few things in your environment that can retard brain development, extremely poor nutrition and lead poisoning be two. Unfortunately, there's no way to improve IQ from it's genetic baseline. All the brain-training, and early intervention stuff shows (very minor) IQ improvement in the short-term, but the effects even out over the participants lives, so it's really just training them to do the tests better, not actually making them significantly smarter.
The Nigerian thing is a myth, it's higher due to sampling bias. The average is still in the 60s when you take the entire population into account.