Question

question 7
1 pts
what is 34,000 in scientific notation with the correct number of significant figures?
3.40 x 10^-4
3.4 x 10^-4
3.4 x 10^4
3.40 x 10^4
question 8
1 pts
a block has dimensions of 6 cm x 7 cm x 6 cm and a mass of 199 g. calculate the density of the block. assume the block is a rectangular, right prism. only write the number value as your answer. the units will be in g/cm^3.

Explanation:

Question 7

Step1: Recall scientific - notation form

Scientific notation is $a\times10^{n}$, where $1\leq a < 10$ and $n$ is an integer. For 34000, we move the decimal point 4 places to the left to get $a = 3.4$ and $n=4$, so it is $3.4\times10^{4}$. Also, 34000 has 2 significant figures, and $3.4\times 10^{4}$ has 2 significant - figures while $3.40\times10^{4}$ has 3 significant figures.

Step1: Calculate the volume of the block

The volume $V$ of a rectangular right - prism is given by $V=l\times w\times h$. Here, $l = 6$ cm, $w = 7$ cm, and $h = 6$ cm. So $V=6\times7\times6=252$ $cm^{3}$.

Step2: Calculate the density

The density $
ho$ is given by the formula $
ho=\frac{m}{V}$, where $m = 199$ g and $V = 252$ $cm^{3}$. So $
ho=\frac{199}{252}\approx0.79$ $g/cm^{3}$.

Answer:

C. $3.4\times 10^{4}$

Question 8