Answer:
140°
Step-by-step explanation:
The other angle inside is 40 so 180-40 is 140°
Answer:



Step-by-step explanation:
Given

Required
Select true inequalities

Subtract 2.1 from both sides

This is true

Open brackets

Subtract 4 from both sides




This is also true
Let x represent the scores. With mean and standard deviation given,
The Empirical rule states that
1) About 68% of the x values lie between 1 standard deviation below and above the mean
2) About 95% of the x values lie between 2 standard deviation below and above the mean
3) About 99.7% of the x values lie between 3 standard deviation below and above the mean
If we consider this rule, then the percentage of scores that fall within 3 standard deviation (-3 to +3) is 99% because this is closer to 99.7%