Answer:
Rock D.
Step-by-step explanation:
We can assume that the force that the catapult does is always the same.
So, here we need to remember Newton's second law:
F = m*a
force equals mass times acceleration.
Where acceleration is the rate of change of the velocity.
So, if we want the rock to hit closer to the catapult, the rock must be less accelerated than rock B.
So, we can rewrite:
a = F/m
So, as larger is the mass of the rock, smaller will be the acceleration of the rock after it leaves the catapult (because the mass is in the denominator). So if we want to have a smaller acceleration, we need to choose a rock with a larger mass than rock B.
Assuming that the mass depends on the size, the only one that has a mass larger than rock B is rock D.
So we can assume that rock D is the correct option.
Answer:
2
Step-by-step explanation:
Answer:
-17 =x
Step-by-step explanation:
144 = -12 (x + 5)
Divide each side by -12
144/-12 = -12 (x + 5)/-12
-12 = x+5
Subtract 5 from each side
-12-5 =x+5-5
-17 =x
Answer:
Step-by-step explanation:
A)
"In the last 2.5 years, the water level has decreased 0.75 feet."
In the very first statement it has been stated that over the last 2.5 years, the water level in a lake has changed by -0.3 feet per year. That means in the last 2.5 years , total decrease in level is as follows
2.5 x - 0.3 = - .75 ft .
So the statement is true.
B)
"The overall change of the water level after 7.5 years will be -2.75 feet."
This statement appears to be false based on information provided
No prediction regarding rate of decrease for a period beyond 5 year has been made so any statement with respect to a timeline of 7.5 years may turn out to be false.
C)
"The change in water level each year for the next 5 years will be -0.4 feet.
"
This statement prima-facie appears to be true because rate of decrease stated in the statement is 0.4 ft /year for next 5 years .
D )
"The overall change in water level for the next 5 years is equal to 5(0.4)"
this statement is true
as change in one year = .4
change in 5 years = 5 x .4