1) Focal length
We can find the focal length of the mirror by using the mirror equation:

(1)
where
f is the focal length

is the distance of the object from the mirror

is the distance of the image from the mirror
In this case,

, while

(the distance of the image should be taken as negative, because the image is to the right (behind) of the mirror, so it is virtual). If we use these data inside (1), we find the focal length of the mirror:

from which we find

2) The mirror is convex: in fact, for the sign convention, a concave mirror has positive focal length while a convex mirror has negative focal length. In this case, the focal length is negative, so the mirror is convex.
3) The image is virtual, because it is behind the mirror and in fact we have taken its distance from the mirror as negative.
4) The radius of curvature of a mirror is twice its focal length, so for the mirror in our problem the radius of curvature is:
Answer:
a)
b)
c)
d)
Explanation:
From the question we are told that:
Population percentage 
Sample size 
Let x =customers ask for water
Let y =customers dose not ask for water with their meal
Generally the equation for y is mathematically given by

Generally the equation for pmf p(x) is mathematically given by

a)
Generally the probability that exactly 6 ask for water is mathematically given by


b)
Generally the probability that less than 9 ask for water with meal is mathematically given by




c)
Generally the probability that at least 3 ask for water with meal is mathematically given by

![p(x\geq3)=1-[p(0)+p(1)+p(2)]](https://tex.z-dn.net/?f=p%28x%5Cgeq3%29%3D1-%5Bp%280%29%2Bp%281%29%2Bp%282%29%5D)
![p(x\geq3)=1-[0.00001+0.0015+0.0106]](https://tex.z-dn.net/?f=p%28x%5Cgeq3%29%3D1-%5B0.00001%2B0.0015%2B0.0106%5D)
![p(x\geq3)=1-[0.0122]](https://tex.z-dn.net/?f=p%28x%5Cgeq3%29%3D1-%5B0.0122%5D)

d)
Generally the mean and standard deviation of sample size is mathematically given by
Mean

Standard deviation


<span>The
formation of the Solar System began 4.6 billion years ago with the
gravitational collapse of a small part of a giant molecular cloud. Most
of the collapsing mass collected in the center, forming the Sun, while
the rest flattened into a proto-planetary disk out of which the planets,
moons, asteroids, and other small Solar System bodies formed.
Hope it helped
</span>
I changed my undershorts. The elastic on the old ones I put on that day was deteriorated, and it completely failed when I dripped lab coffee on it, causing falldown.