Answer: What percentage to save for retirement?
Saving 15% of income per year (including any employer contributions) is an appropriate savings level for many people. Having one to one-and-a-half times your income saved for retirement by age 35 is an attainable target for someone who starts saving at age 25.
Step-by-step explanation: That's the answer I got it right! lol!
(a) The team captain wants to know what his teammates eats before a match
Team captain know by taking a survey of teammates
(b) The team captain wants to know who can score most goals against the best player
This can be known by observation of games. so its observational study
(c) The team captain wants to know how praising the affects the teammates performance.
This can be known by experiment
(d) The team captain wants to know what other sports teammates play
This can be known by observation of games. so its observational study
The parametric equations for x and y describe a circle of radius 10 m, so the length of the base of the fence is the length of the circumference of a circle of radius 10 m. The formula for that circumference (C) is ...
... C = 2πr
... C = 2π·(10 m) = 20π m
The height as a function of angle (t) is found by substituting for x and y.
... h(t) = h(x(t), y(t)) = 4 + 0.01·((10cos(t))²-)10sin(t))²) = 4+cos(2t)
The average value of this over the range 0 ≤ t ≤ 2π is 4, since the cosine function has two full cycles in that range, and its average value over a cycle is zero.
Thus, the area of one side of the fence is that of a rectangle 20π m long and 4 m wide. That will be
... (20π m)·(4 m) = 80π m²
The amount of paint required to cover both sides of the fence is
... 2×(80π m²)×(1 L)/(10 m²) = 16π L ≈ 50.3 L
_____
You can work out the integral for area as a function of t. When you do, you will find it gives this same result.