I read the material, and a good portion of it appears to be at a much lower level than 10th grade, but the mathmatical portion appears to be high school level i

I read the material, and a good portion of it appears to be at a much lower level than 10th grade, but the mathmatical portion appears to be high school level if you stripped a few pieces of this book you would have something around 4-5th grade level ish.