Answer:
C. O.5s
Step-by-step explanation:
If the wave length is 100m and it goes at a speed of 200m/s then it will only take 0.5 seconds because 100 is half of the speed of 200
It takes 42 minutes for 6 people to paint 7 walls
<em><u>Solution:</u></em>
It takes 54 minutes for 4 people to paint 6 walls
To find: Minutes required for 6 people to paint 7 walls
If 
men can do 
work in 
days working 
hours per day and 
men can do 
work in 
days working 
hours per day, then
M = Number of men
D = Number of days
H = Number of hours per day
W = Amount of work
Here in this sum,
<em><u>54 minutes for 4 people to paint 6 walls</u></em>
<em><u>Minutes required for 6 people to paint 7 walls</u></em>
<em><u>Substituting the values in formula, we get</u></em>
Thus it takes 42 minutes for 6 people to paint 7 walls
You can formulate your own equations by analyzing the given problem and its statements. You can do some illustrations so you can understand it better. Introduce some variables and the rest is algebra. For example:
An orange costs $2 while a banana costs $1.5. How many oranges and bananas do you have to buy such that the total cost would equal to $20. You bought a total of 12 fruits.
First, you have to introduce variables. Let 'x' be the number of oranges and 'y' be the number of bananas. One equation you can get from here is knowing the amount of total cost: 2x + 1.5y = 20. Then, the other equation would be knowing the amount of fruits: x+y=12. You have two unknowns and two equations. Hence, you can solve the problem. Solving them simultaneously, you would get that x=4 and y=8.
Answer:
46.5
explanation
6.022*10^23 molecules=40g.
7.00*10^23=40*7.00*10^23/6.022*10^23 g =46.5 g
