Step-by-step explanation:

Answer:
A) [First try is correct for all U1 to U4]
Step-by-step explanation:
1. Trying each option
(let x = 1,2,3,4) since it goes from U1 to U4 (Geometric sequence)
A.) 10(-4/5)^x
10(-4/5)^1 = -8
10(-4/5)^2 = 6.4
10(-4/5)^3 = -5.12
10(-4/5)^4 = 4.096
In 1500 people of 200 lb each, the total weight would be 300000 lb.
Set up a proportion: 200lb/3.2*10^-5 = 300,000lb/x
(3.2*10^-5*300,000)/200 = x
x = 0.48, I believe
The value of x, y and z from the system of equation are -1, -8 and 5 respectively.
Data;
- -2x + 6y + 3z = -31
- -3y + 7z = 59
- 2z = 10
<h3>System of Equation</h3>
To solve this problem, we have to solve the system of equation using substitution method.
From equation (iii)

let us substitute the value of z into equation (ii)

Let's substitute the value of x and y into equation (i)

From the calculation above, the value of x, y and z are -1, -8 and 5 respectively.
Learn more on system of equations here;
brainly.com/question/14323743