Question 561105
Jan 31 is the last day in Jan. So the numbers of days into February is just the Date of the month in February.
For instance, Feb 1 is one day's worth of snow since only one day has past since 31 Jan.
Feb 7 is 7 days worth of snow.

You are told  the depth d, of snow in inches at the base of one ski resort could be approximated by adding 7 to twice the number of days, t, since January 31st.

Let d be the DepthOfSnow
Let t be DateOfMonthInFeb

So deoth of snow can be modeled as
{{{d = (2*t) + 7 }}}

Here is a graph of the snow depth
{{{graph(400,400, -5,28, -5,100, 2x + 7)}}}