Solve the following math problems: 6. Work out the square of: a) 8, b) 15. 7. Complete the sequences: a) 2, 3, 5, 7, ? b) 1, 3, 6, 10, ? c) 2, 4, 8, 16, ? d) 12, 14, 16, 18, ?. 8. Circle all prime num

The square of 8 is $\boxed{\text{64}}$.

b)

The square of 15 is $\boxed{\text{225}}$.

7. Complete the sequences below.

a) The sequence is 2, 3, 5, 7. These are prime numbers.
The next prime number after 7 is $\boxed{\text{11}}$.

b) The sequence is 1, 3, 6, 10. The difference between consecutive terms increases by 1 each time (2, 3, 4).
The next difference will be 5.

The next number in the sequence is $\boxed{\text{15}}$.

c) The sequence is 2, 4, 8, 16. Each term is multiplied by 2 to get the next term.

The next number in the sequence is $\boxed{\text{32}}$.

d) The sequence is 12, 14, 16, 18. Each term increases by 2.

The next number in the sequence is $\boxed{\text{20}}$.

8. Circle all prime numbers.
A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.

a) 2, 1, 6, 5, 9
The prime numbers are $\boxed{\text{2, 5}}$.

b) 5, 6, 9, 2, 11
The prime numbers are $\boxed{\text{5, 2, 11}}$.

c) 9, 15, 11, 7, 5, 3
The prime numbers are $\boxed{\text{11, 7, 5, 3}}$.

d) 9, 8, 11, 12, 10, 8
The prime number is $\boxed{\text{11}}$.

9. Work out the sum of the first 4 odd numbers.

The first 4 odd numbers are 1, 3, 5, and 7.

The sum of the first 4 odd numbers is $\boxed{\text{16}}$.

10. List the multiples of 5 between 1 and 35.

Multiples of 5 are numbers obtained by multiplying 5 by an integer.

The multiples are $5 \times 1 = 5$, $5 \times 2 = 10$, $5 \times 3 = 15$, $5 \times 4 = 20$, $5 \times 5 = 25$, $5 \times 6 = 30$.
The multiples of 5 between 1 and 35 are $\boxed{\text{5, 10, 15, 20, 25, 30}}$.

11. Complete the factor tree below.

a)

The completed factor tree has $\boxed{\text{28}}$ in the top box and $\boxed{\text{7}}$ in the bottom right box.

b)

The completed factor tree has $\boxed{\text{2}}$ in the left box and $\boxed{\text{35}}$ in the right box.