7 The heights that children of a particular age can jump have a normal distribution. On average, 8 children out of 10 can jump a height of more than 127 cm , and 1 child out of 3 can jump a height of more than 135 cm .
- Find the mean and standard deviation of the heights the children can jump.
- Find the probability that a randomly chosen child will not be able to jump a height of 145 cm .
- Find the probability that, of 8 randomly chosen children, at least 2 will be able to jump a height of more than 135 cm .