The equation of a circle:

(h, k) - a coordinates of the center
r - a radius
A diameter d = 2r
We have

Answer: d = 2 · 10 = 20
What is that supposed to mean, it is not a question?
It is -2. This is negative. For instance, if you had 3 candies and your mother took away 5, you would not only have 0 candies, but you would owe your mother 2. This is expressed as a negative number. Please mark Brainliest!!!
Answer:
The null hypothesis is that there is no difference in the mean number of male and female cats
H₀; μ₂ - μ₁ = 0
Step-by-step explanation:
The given parameters are;
The given percentage of male stray cat population = 50%
The given percentage of female stray cat population = 50%
The number of areas the researcher visits, n = 15
The number of stray male cats he finds = 11
The kind of test to be performed = Sign test
The significance level, α = 0.05
A) Therefore the null hypothesis is H₀; μ₂ - μ₁ = 0
The alternative hypothesis is Hₐ; μ₂ - μ₁ ≠ 0.