Hello from MrBillDoesMath!
Answer: 30
Discussion:
The area of a circle of radius R is given by the formula
Pi * R^2
We are given that the area is 225 Pi (Not 255 Pi as stated by the author)
Pi * R^2 = 225 * Pi
Divide both sides by Pi :
R^2 = 225 ---> R = 15
The diameter is twice the radius so the diameter = 30.
Regards, MrB
Answer:
9.54731702 astronomical units
Step-by-step explanation:

Substitute this value in the equation above:

⇒ 
⇒

Hence, its distance from the sun is 9.54731702 astronomical units.
Answer:
96,000
Step-by-step explanation:
To round to the nearest thousand, we need to look at the digit in the hundreds place, which is 6. Since 6 > 5, we know that we need to round up (because 6 is closer to 10 than it is to 0). Currently, the number is 95 thousand so when rounding up, the answer will be 96,000.
Answer:
8 Joule
Step-by-step explanation:
Mass of block = 2 kg
Displacement = x = 800 mm = 0.8 m
Spring constant = k = 25 N/m
Potential Energy of a spring
Work done = Difference in Potential Energy
Work Done = Δ P.E.

⇒P.E. = 0.5×25×0.8²
⇒P.E. = 8 Nm = 8 Joule
Here already the spring constant and displacement is given so the mass will not be used while calculating the potential energy.
Answer:
5x-4y = -32
Step-by-step explanation:
First write the equation in point slope form
y-y1 = m(x-x1)
y - -2 = 5/4 ( x- -8)
y+2 = 5/4 (x+8)
Multiply each side by 4 to clear the fraction
4( y+2 )= 4*5/4 (x+8)
4y +8 = 5(x+8)
4y+8 = 5x+40
Subtract 4y from each side
8 = 5x-4y +40
Subtract 40 from each side
-32 = 5x-4y
5x-4y = -32