Answer:
It will be biased.
Step-by-step explanation:
By surveying only grades 1, 2, and 3, she is not taking a representation of the entire school. It is possible that the popular color or the color the students like would change over time and the opinion of the younger kids could be different from that of the older kids. Therefore, the sample is biased unless she surveys students from all grades.
The best option is the first one (Six yards of rope costs $5.50). It is the lowest unit cost.
<u>Step-by-step explanation:</u>
For the given question case, first we should compare the unit costs of the choices provided and evaluate the best option.
Choice 1:
Six yards of rope costs $ 5.50

Choice 2:
Four yards costs $ 4.75

Thus, the best choice is the first one. Because it is the lowest unit cost.
Answer:
13
Step-by-step explanation:
247/19=13
Answer:
6
Step-by-step explanation:
3-(-3)
3+3
6