Answer:

Step-by-step explanation:
The total surface area can be calculated using the formula

From the diagram

We plug in these values to get;
![S.A=2[5(5)+5(10)+5(10)]](https://tex.z-dn.net/?f=S.A%3D2%5B5%285%29%2B5%2810%29%2B5%2810%29%5D)
![S.A=2[25+50+50]](https://tex.z-dn.net/?f=S.A%3D2%5B25%2B50%2B50%5D)


The father is 27 because when they said 3 TIMES OLDER THEN THE SON he was 9
Answer with explanation:
There are few number of white ball in 10 boxes.
Total number of Black balls in the box=60
So, we have to write number 60 in such a way that, such that it can be represented as sum of ten different digits.
That is the only way by which we can distinguish between ten boxes.
60 =0 +1+2+3+4+6+8+10+12+14
Place these balls in ten different boxes.
So, by this way we can distinguish between boxes.