Why does the acute triangle go under polygon

Three coins are flipped. what is the probability that there will be at least two tails?

What is the average rate of change for this function for the interval from x=2 to x=4 ?

The weight of full–grown tomatoes at a farm is modeled by a normal distribution with a standard deviation of 18.4 grams. the 95 percent confidence interval for the mean weight of the tomatoes is calculated using a sample of 100 tomatoes. what is the margin of error (half the width of the confidence interval)?