Example:
sample density of gasoline, 20 g of weigth into 5 <span>mL
Answer:
D = m / V
D = 20 g / 5 mL
D = 4 g/mL</span>
<u>Answer:</u> The true statement is iron can reduce
to gold metal
<u>Explanation:</u>
Single displacement reaction is defined as the reaction in which more reactive element displaces a less reactive element from its chemical reaction.
The reactivity of metal is determined by a series known as reactivity series. The metals lying above in the series are more reactive than the metals which lie below in the series.

Metal A is more reactive than metal B.
We are given:
Iron can reduce copper, silver can reduce gold, sodium can reduce iron and copper can reduce silver metal.
The increasing order of reactivity thus follows:

where, sodium is most reactive and gold is least reactive
For the given options:
<u>Option 1:</u> Copper cannot easily reduce sodium ion to sodium metal because it is less reactive.

<u>Option 2:</u> Iron cant easily reduce gold ion to gold metal because it is more reactive.

<u>Option 3:</u> Silver cannot easily reduce iron ion to iron metal because it is less reactive.

Hence, the true statement is iron can reduce
to gold metal
Answer:
- <u><em>g) Neither plant should increase by 1 cm in height.</em></u>
Explanation:
See the graph for this question on the figure attached.
The growing of the <em>plant A</em> is represented by the line that goes above the other. At start, that line has a slope that rises about 0.75 cm ( height increase) in 1 day. From the day 2 and forward the slope of the line decreases. The line reaches its highest point about at day 4 and seems to start decreasing. Thus, you should predict that on the day six it <em>most likely </em>does not increase in height.
The growing of the <em>plant B</em> is represented by the line drawn below the other. As for the plant B, the growing decreases with the number of days. Between the days 4 and 5 the line is almost flat, which means that <em>most likely</em> this plant will not grow on the day six or grow less than 0.5 cm.
Thus, for both plants you can say that <em>on day six, most likley, neither should increase by 1 cm in height (</em>option g).