Answer:
45
Step-by-step explanation:

ssubstitute a and b for any of the numbers (3 or 6) and get 36+9 which is 45
45 =

so you would need to find the square root to get c
1 + 1 = 2 - 1 = 1 hope this helps.
Answer:
To express the sum of two numbers using distributive property, we factor out the highest common factor (HCF) of the two numbers (i.e. the greatest number that can divide the two numbers without remainder)
28 = 2 x 2 x 7
42 = 2 x 3 x 7
The HCF of 28 and 42 is given by 2 x 7 = 14
Therefore, we express 28 + 42 using distributive property thus: 14(2 + 3)
It is not possible to select a single group from the primary school, since being a single group it could not in any way represent the entire primary school.
Choosing a group would provide the average height for that group, not the entire primary.
Assumptions can be made that the course of half of the primary would theoretically give us a more accurate representation, but the objective is to select a number of students from each course and there would be a representative sample of the entire primary.