12.
1: n•n= n^2
2: n•(-2)= -2n
3: 2•n= 2n
4: 2•(-2)= -4
=n^2-2n+2n-4
= n^2-4
12h + 20t = income
1.5(h + t) + 7h + 9t + 500 = expenses
12h + 20t - 1.5(h + t) + 7h + 9t + 500 > 0
We know that
<span>20% --------------> were blue
</span><span>1/10---> 0.10----> 10%--------------> were white
</span><span>40% ---------------> were silver
</span>
and
<span>9 ---------> were gold
so
gold=100%-(20%+10%+40%)-------> 100%-70%------> 30%
30% ---------------------> is equal to 9
10% (</span>were white)<span>-------> X
X=10%*9/30%------> x=3
the answer is
3</span>
Answer:
B. A water wheel in a dry river
Step-by-step explanation:
Work is said to be done when a force moves a body or an object through a certain distance in the direction of the force. Thus for work to be done, force and distance are required.
i.e Work done = Force x distance
It is measured in Joules.
Also, the work done by an object could be a measured of potential energy.
So that,
Work done = potential energy = mass x gravitational force x height
Considering the collage in the question, since the water wheel is in a dry river no work is done. Water wheel is a device that functions through the flow of water body, thus causing its rotation.
Answer: C. 18.8w
Step-by-step explanation:
Since Toby exercise 14hours a week, and John exercises 20% more than Toby
John increment in number of hours compared to Tobi will be;
20/100 ×14 = 2.8hrs
This shows John exercises 2.8hrs more than Tobi. Total number of hours exercised by John will become;
14+2.8 = 16.8hrs
Since Jenny exercises two more hours than John, Total number of hours exercised by Jenny will be;
16.8hrs+2hrs
= 18.8hrs/week
If Jenny exercise 18.8hrs in a week, it means she will exercise 18.8×w/1 in w weeks which gives 18.8w weeks.
