Humans please help me

How do you say nesscesery and expainitary

After applying the composition r0.90 ry to rs what are the coordinates of r' and s'? a. r'(–3, 1),  s'(–3, 5)b. r'(–1, 3),  s'(–5, 3)c. r'(1, 3),  s'(5, 3)d. r'(5, 3),  s'(1, 3)

Which mathematical statements are true? 1) if 3 is an odd number, then 3 times 3 is an even number. 2) if 6 is less than 7, then 4 is greater than 7. 3) six is divisible by 3, and 10 is a multiple of 2. 4) the average of the data is greater than the largest value in the data, or it’s less than the largest value in the data. 5) the slope of a linear graph is its rate of change, and the graph’s y-intercept is the initial value. 6) if an equilateral triangle has equal angles, then all its angles will measure 45°.

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?