Answer:
D
Step-by-step explanation:
Ok, so 11:9
11-9 = 2
which means that 124= 2:1
124/2 = 62
so 62:0
now 11 x 62= 682
9 x 62= 558
so the ratio is 682:558
now 682 + 558 = 1,240
There are 1,240 total students in the school. 682 boys and 558 girls
It is located in Wisconsin, I don't know the second question
Answer:
± 
, 
Step-by-step explanation:
See the attached image
This problem involves Newton's 2nd Law which is: ∑F = ma, we have that the acting forces on the mass-spring system are:
that correspond to the force of resistance on the mass by the action of the spring and
that is an external force with unknown direction (that does not specify in the enounce).
For determinate
we can use Hooke's Law given by the formula
where
correspond to the elastic constant of the spring and
correspond to the relative displacement of the mass-spring system with respect of his rest state.
We know from the problem that an 15 Kg mass stretches the spring 1/3 m so we apply Hooke's law and obtain that...

Now we apply Newton's 2nd Law and obtaint that...
±
= 




Finally...
± 
We know from the problem that there's not initial displacement and initial velocity, so...
and 
Finally the Initial Value Problem that models the situation describe by the problem is
