Answer:
$74.90
Step-by-step explanation:
If $70 is your original price, you would need to multiply it by 1.07, because that is 107%.
Since the original price is 100% of the price, and sales tax is another 7% of the price, you are multiplying the original price by 107%, again making $74.90.
Do you understand?
Answer:
It will take them 3.43 hours.
Step-by-step explanation:
Let T denote the total cookies that need to be cocked. Observe that:
- If Rosanne finishes the cookies in 6 hours, that means that she can make
cookies per hour. - If Dorothy finishes the cookies in 8 hours, that means that she can make
cookies per hour.
Then, by 1) and 2), if they work together would we able to make

cookies per hour.
Therefore, in order to finish the T cookies they will need 
It would be written as:
5.65 *10^-4
Remember, when writing scientific notation for a decimal, the power of 10 is always negative. In this case, since we're basically moving the decimal point for places to the right, the power of 10 is -4
Hope this helped! :)