The answer is Identity property of multiplication
A chlorine nucleus will contain: Number of protons Z = 17. Number of protons + neutrons A = 35. Number of neutrons N = 35 - 17 = 18.
Answer:
A. The "9" in the second number represents 10 times as much as the "9" in the first number.
Step-by-step explanation:
If you look at the "9" in the first number as 90 and multiply that by 10, you will get 900. In the second number, the "9" is in the 100's place.
Answer:
537.2 ft^2
Step-by-step explanation:
For this problem, we need to find the area of both the inner and outer circle and subtract the area of the outer circle from the area of the inner circle.
The equation for the area of a circle is:
A = πr^2
So we are given the diameters of the circles. We know that the diameter of a circle is twice the radius.
Let's find the area of the 10ft diameter circle:
A_Little = π(10/2)^2 = π(5)^2 = 25π
Let's find the area of the 28ft diameter circle:
A_Big = π(28/2)^2 = π(14)^2 = 196π
So the area of the big circle excluding the inner circle would be as follows:
196π - 25π = 171π
So 171π in terms of decimals rounded to the nearest tenth would be 537.2.
Cheers.
We calculate the speed by dividing the distance over time:
s = d/t
So the distance described in the problem is always the same, A to B and B to A.
But we are told that;
7 = d/t
7 = 2d/(t + 2)
that is, the first equation say that at speed 7 km/h a distance d is walked in a time t
the second equation say that at a average speed of 7 (that is 8 on one way and 6 in the other: 8 + 6 = 14, half of it), twice the distance is walked in a time equal to the first time plus 2 minutes.
So we have a system of linear equations, 2 of them with two unknowns, we can solve that:
7 = d/t
7 = 2d/(t + 2<span>)
</span>lets simplify them:
7t = d
7(t + 2) = 2d
7t = 2d - 14
we substitute the first in the second:
<span>7t = 2d - 14
</span><span>7t = d
</span>so:
d = 2d - 14
d = 14
so the distance between A and B is 14 km
