Factorise the following.​

iii. (l + m - n)(l - m + n)

vi. (5a -b) ( 5b - a)

Step-by-step explanation:

iii. l² - (m - n)²

= (l + m - n)(l - m + n)

vi. 4(a+b)² - 9(a-b)²

= (2(a+b))² - (3(a-b))²

= (2(a+b) + 3(a-b)) (2(a+b) - 3(a-b))

= (2a+2b + 3a - 3b) (2a+2b - 3a + 3b)

= (5a -b) ( 5b - a)

what "following statement"?

step-by-step explanation:

whole numbers.

step-by-step explanation:

we are given the average monthly rainfall (in millimeters) model r(m) for the years 1900-2009 as a function of the month number m.

as we can see m is taken for the number of months for years 1900-2009.

we know that number of months can't be a negative number or decimal number or a fraction.

so, the number of months could be only positive whole numbers.

therefore, whole numbers is more appropriate for the domain of r.