Answer:
(A) 8.8 years
Step-by-step explanation:
Given that the principal amount = $ 3100
Rate of compound interest = 8% compounded semiannually.
The given formula is

Where A is the final amount, P is the principal amount, r is the rate of compound interest, t is the time and n is the number of times per year the interest is compounded.
From the given condition,
P=$3100
r= 8%=0.08 compounded semiannually
n=2
A=2 x 3100=$ 6200.
Put all these in the given formula to get the required time, we have



On rounding to the nearest tenth of a year, t=8.8 years.
So, the invested amount will be double in 8.8 years.
Hence, option (A) is correct.
Answer:
99 (cm^2)
Step-by-step explanation:
Perpendicular to the AB segment at points D and C, the graph is divided into two triangles and a rectangle.
The area of the middle rectangle is equal to 8*9=72. The hypotenuse of the right triangle is 10cm, and one of the right sides is 9cm, so the other side is SQRT (10^2-9^2) = SQRT (19).
One side of the left triangle is 9cm long and the other side is 14-8-sqRT (19) = 6-sqRT (19) cm.
Then, add the area of the three parts.
72+9*sqrt(19)/2+9*(6-sqrt(19))/2=99 (cm^2)
The earth is 93 million miles away from the sun. 93 million times 10 is 930,000,000 away. Mars is currently 141.6 million miles from the sun. Assuming the planets were in a straight line you would subtract from 141.6 million miles the 93 million miles so that would put us within 48,600,000 miles of Mars. So the answer is we would be closest to Mars.
Answer: Jennifer didn't randomly assign participants to the control and experimental group.
Step-by-step explanation: In the scenario discussed above, Jennifer failed to perform a random assignment of the participants who took part in the survey, that is the experimental group, those who receive the treatment and the control group, those who don't. Random assignment is required in other to address the issue of bias in our experiment. She was supposed to perform a random assignment of the participants to the two groups instead of asking them to make a choice.
Answer:
0.625
Step-by-step explanation:
5/8 is the same as dividing so divide them both and it will equal 0.625