Answer:
a) See the file below, b)
, c) 
Step-by-step explanation:
a) Points moves clockwise as t increases. See the curve in the file attached below. The parametric equations describe an ellipse.
b) The arc length formula is:
![s = \int\limits^{0.5\pi}_{-0.25\pi} {[\left( 3\cdot \cos t\right)^{2}+\left(-5\cdot \sin t \right)^{2}]} \, dx](https://tex.z-dn.net/?f=s%20%3D%20%5Cint%5Climits%5E%7B0.5%5Cpi%7D_%7B-0.25%5Cpi%7D%20%7B%5B%5Cleft%28%203%5Ccdot%20%5Ccos%20t%5Cright%29%5E%7B2%7D%2B%5Cleft%28-5%5Ccdot%20%5Csin%20t%20%5Cright%29%5E%7B2%7D%5D%7D%20%5C%2C%20dx)
c) The perimeter of that arc is approximately:


Let the number = x
11x is 11 times the number. You are to take 6 less than this. Be careful how you read six less. It means the 6 is subtracted from the 11x
11x - 6 This is what you finally get.
You have to separate 3 five times so like 3+3+3+3+3=15
Four possible way depending on what you spin if it is dominoes it would be twelve