The resultant in the x-direction:
Rx = F1 + F2 = 2.5 N - 1 N = 1.5 N .
The resultant in the y-direction:
Ry = F3 + F4 = 2 N - 3 N = -1 N.
Apple on tree branch has potential energy
Answer: (a) Z-score are 1 and -1.2 for northern and southern regions, respectively.
Explanation: <u>Z-score</u> is how many standard deviations a data is from the population mean or how far a data point is from the mean.
The z-score is calculated by the following:

where
x is the data point
μ is population mean
σ is standard deviation
For the <u>northern</u> <u>region</u> birds:
μ = 10, σ = 3, x = 13

z = 1
The z-score for birds living in the northern region is 1, which means it is 1 standard deviation <em>above the mean</em>.
For the southern region:
μ = 16, σ = 2.5, x = 13

z = -1.2
The z-score for southern living birds is -1.2, meaning it is 1.2 standard deviations <em>below the mean</em>.
Answer: Work done by the box will be 8 Joules.
Explanation:
Work done by a substance is the product of the force applied on it and the displacement of a substance.
Mathematically,

Where,
W = work done = ? J
F = Force applied = 4 N
s = displacement = 2 m
Putting values in above equation, we get:

Hence, work done by the box will be 8 Joules.