The formula for the standard error is this:
σM = σ / √N
where
σM is the standard error
σ is the standard deviation
N is the number of samples
So,
σM = 0.45 / √50
σM = 0.0636 or 6.36%
The standard error is 0.0636
First, distribute the (1/2) into (4x+12) by multiplying them.
The equation becomes:
2x + 6 + 5x = 30
On the left side, combine “like terms” through addition.
7x + 6 = 30
Subtract 6 from both sides:
7x = 24
Finally, get x alone by dividing both sides by 7:
x = 24/7, or if you wanted to round the decimal answer, it’s about 3.429.
Yes it is a least 75 stories tall and.....
Answer:

Step-by-step explanation:
Use distributive property: 
What is -x * x^2? Answer: -x^3
What is 3 * x^2? Answer: +3x^2
What is -x * -4x? Answer: +4x^2
What is 3* -4x? Answer: -12x
What is -x * -6? Answer: +6x
What is 3 * -6? Answer: -18

Combine like terms, and your answer would be....

Hope this helps :)
Have a great day!