Answer:
2g/mL^3
Step-by-step explanation:
To find density, we use mass/volume. 40g is the mass and 20mL is the volume. 40/20 is 2, therefore, 2g/mL^3
Answer:
136x+100
Step-by-step explanation:

Hope this helps!
Answer: There are 2346953264 ways to do so.
Step-by-step explanation:
Since we have given that
Total number of selected countries = 12
Number of selected countries from a block of 45 = 3
Number of selected countries from a block of 57 = 4
So, remaining number of selected countries from a block of 69.
So, 12-(3+4)=12-7=5
Now, we need to find the number of ways, so we will use "Combination" to select that number of countries.
So, it becomes.

Hence, there are 2346953264 ways to do so.
102 because it’s kind of like a 180 but not I’m direct form