[1] Billy already had some money saved. He worked for 10 weeks over the summer, saving the same amount of money each week. After 3 weeks his savings total was $1,175.
After 7 weeks his sayings total was $1,675.
a) How much money did Billy have in savings before he started his summer work?
b) How much money did Billy have in savings after 10 weeks?

answer: it is d

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.