Aconsultant has three sources of income—from teaching short courses, from selling computer software, and from advising on projects. his expected annual incomes from these sources are $7,000, $22,000, and $50,000, and the respective standard deviations are $3,000, $4,000, and $18,000. assuming independence, find the mean and standard deviation of his total annual income.

Mean = $79,000

Standard deviation = $25,000

Step-by-step explanation:

Data provided in the question:

Expected annual incomes:

From teaching short courses = $7,000

From selling computer software = $22,000

From advising on projects = $50,000

Standard deviation:

teaching short courses = $3,000

selling computer software = $4,000

advising on projects = $18,000

Now,

it is given that the events are independent

therefore,

Mean = ∑(Expected annual income)

or

Mean = $7,000 + $22,000 + $50,000

or

Mean = $79,000

also,

Standard deviation = ∑(standard deviation)

or

Standard deviation = $3,000 + $4,000 + $18,000 = $25,000

answer: the answer is (b) amie should have multiplied

step-by-step explanation: given a sphere and a cylinder with same radius and height.

let, 'r' be the radius of the cylinder and sphere and 'h' be the height of the cylinder. according to the question,

r = h.

now, the volume of the sphere will be

and the volume of the cylinder will be

therefore, we have

thus, ammie should have multiplied the volume of the sphere

no because after the troops were pulled many blacks were killed by hangings lynchings and other cruel ways which in a way interrupted the reconstruction of the south and differed from the way abraham lincoln had an idea of reconstruction