20 POINTS Use algebra tiles to find the difference. Let one white tile equal +1 and one black tile equal –1. 12 – (–9

3
21
23
−21

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)?

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

Find the constant of variation for the relation and use it to write an equation for the statement. then solve the equation.