<h3>3
Answers: B, C, F</h3>
Each of these are closed figures formed by straight line segments. Think of fencing in an area (not necessarily a rectangle) using various straight fence sections. The length of each section does not have to be the same.
Side notes:
- Choice A is not a polygon because the figure is not closed.
- Choice D is not a polygon because it is not composed of line segments only. Choice D is an ellipse instead.
- Choice E is not a polygon due to the curved portion.
Answer:
False, they take form of a U shape
Answer:
3 more students need to sign up
Step-by-step explanation:
Let the equal number of students in 9 teams be x.
Total number of signed up students = 690.
Let t be the required number of students to be signed.
Therefore, 9x = 690+t.
This means, 690+t is a multiple of 9.
The least value of t to make 690+t, a multiple of 9 is 3 and hence,
= 77
Hence, 3 more students need to sign up and each of the 9 teams consists of 77 students.
In fact, this problem belongs to the chemistry section. Recall that many other sciences require mathematical calculations. The problem will belong to Mathematics only if no knowledge of other sciences are required to solve the problem.
Solubility for the given substances is measured in grams per 100 g of water at a particular temperature (20 deg.C).
This means that the mass (assumed to be the solute) will not change the solubility, just the minimum quantity of solvent (water) will.
Thus the solubility of sodium chloride will remain L=36 g/100g H2O for any quantity of solute. Similarly, the solubility of lead nitrate will remain as K=54 g/100 g H2O.
The reason that they remain constant is because the quantity of solvent (water) is fixed at 100 g. Varying amount of solute will affect the quantity of solvent required, but not the solubility.
I'll leave it to you to calculate the difference between K & L.
