Answer:
The six-row combin harvests 285 bushels of corn per hour.
Explanation:
The rule of three or is a way of solving problems of proportionality between three known values and an unknown value, establishing a relationship of proportionality between all of them. That is, what is intended with it is to find the fourth term of a proportion knowing the other three.
If the relationship between the magnitudes is direct, you can apply the following formula:
a ⇒ b
c ⇒ x
So: 
In this case you can apply it in the following way: if 56 pounds is equal to 1 bushel, 266 pounds to how many bushels is it?

x=4.75
This is, a six row combin harvests 4.75 bushels of corn per min.
So, being 1 hour equal to 60 minutes, you can apply the following rule of three: if in 1 minute a six-row harvester harvests , in 60 minutes how many bushels of corn it harvests?

bushels of corn= 285
<u><em>
The six-row combin harvests 285 bushels of corn per hour.</em></u>
Zero order are reactions in which concentration of reactant has NO effect on RATE OF REACTION.
2. First order are reactions in which concentration of one reactant is proportionate to the RATE OF REACTION.
Exp: That means when you increase the concentration of the one reactant, then the rate of reaction will increase by the same degree of extent.
3. Second order are reactions in which concentration of two reactant has an effect on the RATE OF REACTION.
Formula:
1. Zero order Rate = k
2. First order Rate = k(A)^m
3. Second order Rate = k(A)^m(B)^n
where () represents concentration
and equation is mA + nB -> Product.
The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
Tollen's test is an organic test that determines whether the sample is an adehyde or not. When aldehydes are present, the reaction forms a silver compound which refers to the other name of Tollen's as silver mirror test. The aldehyde among the choices is C. pentanal
The idea here is that you need to figure out how many moles of magnesium chloride,
MgCl
2
, you need to have in the target solution, then use this value to determine what volume of the stock solution would contain this many moles.
As you know, molarity is defined as the number of moles of solute, which in your case is magnesium chloride, divided by liters of solution.
c
=
n
V
So, how many moles of magnesium chloride must be present in the target solution?
c
=
n
V
⇒
n
=
c
⋅
V
n
=
0.158 M
⋅
250.0
⋅
10
−
3
L
=
0.0395 moles MgCl
2
Now determine what volume of the target solution would contain this many moles of magnesium chloride
c
=
n
V
⇒
V
=
n
c
V
=
0.0395
moles
3.15
moles
L
=
0.01254 L
Rounded to three sig figs and expressed in mililiters, the volume will be
V
=
12.5 mL
So, to prepare your target solution, use a
12.5-mL
sample of the stock solution and add enough water to make the volume of the total solution equal to
250.0 mL
.
This is equivalent to diluting the
12.5-mL
sample of the stock solution by a dilution factor of
20
.