Answer:
The distance between the slits is given by 1.3 ×
m
Given:

D = 4 m
y = 
m = 1
To find:
distance between slits, d = ?
Formula used:
y = 
y = distance of first bright band from central maxima
D = distance between screen and source
d = distance between slits
= wavelength
Solution:
distance of first bright band from central maxima is given by,
y = 
y = distance of first bright band from central maxima
D = distance between screen and source
d = distance between slits
= wavelength
Thus,
d = 
d = 
d = 1.28 × 
d = 1.3 ×
m
The distance between the slits is given by 1.3 ×
m
I think the situation is modeled by the scenario in the attached image. Some specific values seem to be missing (like the height of door
)...
The door forms a right triangles that satisfies

We also have

so if you happen to know the height of the door, you can solve for
and
.
is fixed, so

We can solve for the angular velocity
:

At the point when
and
ft/s, we get

Some substances look alike and the density can help you determine which is which. It also helps to tell which is heavier than the other.
Near Greenland in the northern hemisphere <span />
Answer:
Farmers
Explanation:
At the time of founding our country most soldiers in the revolutionary war were farmers who were inexperienced.