Answer:
从 1 到 20 有 8 个素数。它们列在下面:2、3、5、7、11、13、17 和 19。
Answer:
28, 29, and 30
Step-by-step explanation:
There's probably better ways but you can estimate by knowing 30*3=90 so it should be somewhere pretty close to 30. Guess and check with basic calculations to get 28, 29, and 30.
Certain, as long as the student was studying using useful techniques that worked for them and paid close attention to the material taught in class
Answer:

Step-by-step explanation:
since
, We can substitue for 
Answer:
The price of price of the stock after it has been owned for 12 weeks is $92.55
Step-by-step explanation:
Given: The price of a particular stock is represented by the linear equation
y = -0.91x + 103.47
where x represents the number of weeks the stock has been owned and y represents the price of the stock, in dollars.
We have to find the price of price of the stock after it has been owned for 12 weeks.
Since , x represents the number of weeks the stock has been owned.
Thus, by substitute, x = 12
We get the value of y , the price of stocks.
Thus, y(x) = -0.91x + 103.47
⇒ y(12) = -0.91(12) + 103.47
⇒ y(12) = -10.92 + 103.47
Solving , we get,
⇒ y(12) = 92.55
Thus, the price of price of the stock after it has been owned for 12 weeks is $92.55.