Answer:
1. The required slope m, for the context is

2. The y-intercept in the context is

3. The x-intercept of the linear model is

Explanation:
Given:

Where,
is the number of phones.
d is the number of days he has worked that week.
This is a linear model type equation.
Can be represented in the slope intercept form which is equal to

Where,
m = Slope of the line.
c = y-intercept.
Now if we compare the given model by slope intercept formula we get

So ,the slope in the context of the problem is
.
and the y intercept in the context of the problem

For finding x-intercept put y = 0
Here,


So, the x intercept of the linear model is
