The very first one (the very left one)
        
             
        
        
        
Answer:
Astronomers were trying to find the weight of six planets - Mars, Venus, Pluto, Jupiter, Mercury, and Saturn. The number of planets lighter than Mars was equal to the number of planets heavier than Venus. Saturn was heavier than Mars and Mercury were heavier than Pluto. Venus was lighter than Mars. Saturn was not the heaviest planet.
Step-by-step explanation:
 
        
             
        
        
        
The rule to remember about generating the perpendicular family to a line is we swap the coefficients on and x and y, remembering to negate one of them. Then the constant is set directly from the intersecting point.
So we have
y = 3x + 2
-3x + 1y = 2
Swapping and negating gets the perpendiculars; the constant is as yet undetermined.
1x + 3y = constant
Since we want to go through (0,2), we could have just written
x + 3y = 0 + 3(2) = 6
3y = -x + 6
y = (-1/3) x + 2
Third choice
 
        
             
        
        
        
Answer:
(B) 20
Step-by-step explanation:
Let small puppet be represented by-----------------s
Let large puppet be represented by-----------------l
Total number of puppets expression will be: s+l =25---------a
The expression for total costs will be : 1$ s + $2l=$30-------b
Equation a can be written as; s= 25-l ------------c
Use equation c in equation b as
$1( 25-l )+$ 2l = $30
25-l + 2l = 30
25+l =30
l= 30-25 =5
l, large puppets = 5 
s, small puppets = 25-5 = 20 
Answer choice A is incorrect because 25 is the total number of all puppets
Answer choice C and D are incorrect because the numbers are less that that of small puppets.
 
        
             
        
        
        
Answer:
18 gallons
Step-by-step explanation:
We'll find out how much of the total container was lost when pouring out by subtracting 2/3 from 1/2.
2/3 = 4/6
1/2 = 3/6
4/6 - 3/6 = 1/6
1/6 of the total amount the container could hold was lost when 3 gallons was poured out. This means that 1/6 of the container equals to 3 gallons. We can then simply multiply 3 by 6 to find the number of gallons of liquid the container can hold.
3 * 6 = 18 gallons
Checking my answer:
18 * 2/3 = 6 * 2 = 12
12 - 3 = 9
1/2 of 18 = 9
This means that our answer is correct.