What are co-primes? Give examples of five pairs of co-primes. Are co-primes always primes? If no, illustrate your answer by an example.

Express the following number as the sum of two odd primes.

$36$

Express the following number as the sum of two odd primes.

$42$

Express the following number as the sum of two odd primes:

$84$

Express the following number as the sum of two odd primes:

$98$

Express the following odd number as the sum of three odd prime numbers.
$35$

Express the following odd number as the sum of three odd prime numbers.
$49$

Express the following odd number as the sum of three odd prime numbers.
$63$