You haven't told us what the passing percentage is on the exam,
or what the passing percentage is for the semester, or any of that.
For number one the answer is Iodine because it is in the same group as fluorine. For number two the answer is Germanium for the same reason. For number three the answer is Aluminum for the same reason.
We know, weight = mass * gravity
10 = m * 9.8
m = 10/9.8 = 1.02 Kg
Now, Let, the gravity of that planet = g'
g' = m/r² [m,r = mass & radius of that planet ]
g' = M/10 / (1/2R)² [M, R = mass & radius of Earth ]
g' = 4M / 10R²
g' = 2/5 * M/R²
g' = 2/5 * g
g' = 2/5 * 9.8
g' = 3.92
Weight on that planet = planet's gravity * mass
W' = 3.92 * 1.02
W' = 4 N
In short, Your Answer would be 4 Newtons
Hope this helps!
Question 25 Answer: Destructive interference occurs.
<span>Question 26Answer: The waves are closer together (as they move) because the object is moving toward you.</span>
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It depends where you are.
-- If you weigh 120 pounds on the Moon,
then your mass is 329.1 kilograms.
-- If you weigh 120 pounds on Mars,
then your mass is 143.8 kilograms.
-- If you weigh 120 pounds on the Earth,
then your mass is 54.4 kilograms.